This self publishing blog was inspired by all of the e-mail questions I've received about the print on demand publishing model I advocate in my book. While I learn a great deal from reader feedback, some of the questions just repeat themselves over and over again, just like bloggers. I've covered most of the common questions over the past three months with individual posts, but I thought I'd rank them here with a couple of links for each. Without further ado, the top five questions are:
1) How can I sell more books?
My favorite answer is online book marketing but the caveat is it may already be too late in the self publishing process if you've published a book for which there's no market. As a self publisher, you are the acquisitions editor, and you can't pretend you're running a publishing business if you're willing to publish anything you write. Print on demand makes it extremely inexpensive to publish books, but selling books is another matter.
2) How do I start a self publishing company?
The first step is obtaining ISBN numbers without which you are an author, rather than a publishing company. Next comes sitting down and deciding what you are hoping to accomplish by starting your own publishing house. Take a lesson from publishing industry numbers and then, before you give up all hope, contrast the results with working as a trade author.
3) Should I use a subsidy publisher?
There's no shame in signing up with a subsidy publisher, but it's important to realize you are being published by them as opposed to self publishing. Subsidy presses will publish anything, from fiction and how-to books to poetry and memoir. There are subsidy presses that specialize in Christian books and some that only publish cookbooks. What they all share in common, whatever their fees and contracts, is that none of them provide any effective book marketing, and in the aggregate, they sell very few books.
4) Should I use print on demand?
Print on demand gives publishers the ability to cost effectively print one book at a time, but it's the vertical integration of printing and distribution that makes it a viable model. Currently, the best option for self publishers working with print on demand is Lightning Source, but they currently have limitations with illustrations and greyscale graphics, which I try to avoid entirely.
5) Should I publish e-books?
Once you are set up as a self publisher using print on demand, publishing e-books is easy, and there's little reason to set up your own e-book server and software. There are different design considerations to look at, especially with e-book covers. The problem with e-books is that they are not huge sellers, though Amazon is striving to change that with their new Amazon Shorts e-books and by concentrating e-book sales in the U.S. store.
Print on Demand Self Publishing
Book Publisher vs Book Printer
Authors new to self publishing often confuse the role of a book publisher with that of a printer. In fact, these two businesses have about as much in common as farming and running a restaurant. Yes, both publishers and printers deal in books, but publishers don't own printing presses and printers don't file for copyrights. To put it as crudely as possible, printing books is essentially a value-added paper business. Printers take two commodities, paper and ink, and add value by putting the two together. The more books you buy from an offset printer, the cheaper they get, until the price starts to approach the value of the paper, ink, amortization of the press and labor. Below that they'd be selling at a loss. Publishers, at the lowest common denominator, are intellectual property holding companies. If you want an unflattering characterization of a big trade publisher, think of an opportunistic law firm with a large marketing department attached.
The main reason it's now easier than ever to confuse a book publisher with a book printer is that a huge market has crept up for middlemen who in truth are neither one nor the other. In the old publishing world of offset printing, packaged subsidy publishing deals for authors and so-called "self publishing companies" existed, but their prices started in the thousands of dollars due to the high printing costs involved. Equally important, those traditional subsidy publishers (also called vanity presses though I don't think it's a good description) couldn't do much to make their authors’ books available through distribution. Thus, authors who did their homework could quickly figure out that they were throwing their money away on a dream, with practically zero chance of selling books.
In the past decade, print on demand and internet bookselling have changed the game for authors, whether they set out to make a living through self publishing or they just want to see their book in print. By allowing the books to be printed one at a time, print on demand changed the minimum cost to get a book "into print" from over a thousand dollars to less than a hundred. At the very same time print on demand technology was becoming a reality, the internet opened up a whole new way to market and sell books that could completely bypass traditional book distribution and retail outlets. Like them or hate them, Amazon is now the worlds largest bookstore, and every book publisher can get their books listed by Amazon.
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A whole new crop of subsidy publishers, companies which charge an author a fee to get their book in print, have sprung up to take advantage of the Lightning Source business model. These companies are all middlemen, and for the authors who merely want to see their books in print and available through Amazon and distribution, the better ones offer a low cost way of doing this. However, it's important to understand that apart from charging authors a fee rather than paying an advance, subsidy publishers differ from traditional book publishers in one critical way. They lack a marketing department, which means, unless the author does all of the marketing, there won't be any sales to speak of. Some subsidy publishers offer marketing services, for which they charge, but I've never seen any evidence that those marketing services can generate enough sales to pay back a significant fraction of their costs. It's money thrown away. Even worse, some subsidy publishers emulate traditional book publishers and they take the intellectual rights to the book by contract. Whatever you do, never sign a contract with a subsidy publisher who claims any rights at all to your book. Charging you to take ownership of your intellectual property is just adding insult to injury.
Print on demand has been a tremendous boon to both subsidy published authors, who can now get their books in print for hundreds rather than thousands of dollars, and for self publishers. True self publishers can now cut out the middleman and start earning significant money on every book they sell without having to invest in a garage full of books and a shipping and handling operation. All that's required to become a book publisher today is a typeset manuscript and cover in PDF format, an on demand book printer with distribution, and an ISBN block. Of course, if you want to make a living publishing books, you need to market them, because nobody is going to beat a path to your door. I'm a huge advocate of Internet marketing for self publishers, because with a little web savvy, many non-fiction titles make terrific web content that will draw visitors and buyers to a website. I was so taken by the new model that I stopped selling my manuscripts to trade publishers and started publishing them myself, including my latest title, "Print on Demand Book Publishing - a New Approach to Printing and Marketing Books for Publishers and Authors."
Services Self Publishers Can Afford to Outsource
Relatively few self publishers can produce a book entirely by themselves. I've gotten to the point where I'll do the entire layout and cover design, but I always hire an editor and a number of proofreaders. There are some excellent writers who may be comfortable editing themselves, but most writers can't even proofread an e-mail, so proofreading your own book is just nuts. You can outsource a certain amount of market research, though I don't really recommend it, and hiring illustrators or a photographer is also common. Of all the self publishing services I've seen offered, marketing is the one I'm most skeptical of. Promoting your books is the main job of the self publisher. If you have to outsource that, you probably aren't going to make it.
How much a self publisher can afford to spend on outsourced publishing services depends entirely on the future sales of the book. The problem with this if you are a first time publisher is you can't possibly estimate how many copies you are going to sell. My rule of thumb for self publishing is that any book that sells over 2,500 copies a year is doing terrific. Titles selling between 1,000 copies and 2,500 copies are doing good, and those selling between 500 copies and 1000 copies aren't too shabby. The average self published book probably sells much less than 500 copies a year, which means it would be hard to justify a lot of outsourced expenses to get it into print. I'm sure everybody reading this assumes that their first book will be one of the ones to sell over 2,500 copies a year, even 25,000 copies a year, and while that may happen, it's like counting on winning a lottery ticket. The number of books any given title sells is simply much lower than most authors think.
Getting back to self publishing services, the most indispensable one is proofreading. Nobody publishes perfect books, many non-fiction trade books I've read average an error every ten pages or so, but that's hardly an ideal yardstick to measure yourself against. If you have friends and family willing to read your manuscript for free, take advantage, but it's critical to give them the book in its final typeset form. Last minute changes and edits are probably the main source of errors in professionally produced books, and the way to avoid this is not to rush to the proofreading phase until the book is truly finished. In addition to free proofreaders, I always hire local college students and pay $10 or $15 an hour to get some extra eyes on the job.
Competing for second in importance of the self publishing services you can outsource are editing and cover design. It's not that I believe cover design is more important than interior layout, to the contrary, but it's easier for most self publishers to learn how to do a passable job on layout than on cover design, and cover design is also cheaper. Cover designers who do a reasonable job abound on the Internet, prices range from around $99 to around $299, for which you may even be able to get your feedback incorporated into the design. Local designers are more likely to charge by the hour, and however low their basic rate, it will quickly add up to $500 or more if you start making changes. Editing, on the other hand, is always charged by the hour or based on the count of pages or words. I've paid anywhere from $15 to $25 an hour for editing, based on the editor's experience, which means anywhere from $500 to $1500 for paperbacks in the 40,000 to 80,000 word range.
Hiring an interior designer can be highly problematic, and I'd only recommend paying by the hour with tight limits or a low page rate, not much over a dollar a page a book consisting of text. Graphic artists who do book design as a sideline are happy to charge from $5 to $10 a page, which quickly gets you into the $1,000 range for something most readers will never notice as long as the job is moderately competent. It's also relatively easy to learn how to produce a book block directly out of your word processor, but it's definitely worth reading a book or two on the subject first to aid you with font selection and basic layout decisions.
Unfortunately, authors who rush into self publishing when they can't find a trade publisher for their first book typically pay for all of the publishing services above, and pay top dollar at that. Add the cost of an ISBN block and setting up the book with a print on demand printer like Lightning Source or Booksurge and you've invested around $5000 without selling your first book. That's cheap by trade publishing standards, but the average self published book will never earn that back. Self publishers whose books fail to sell often blame the cover designer, the book chains, lack of access to distribution, but there's only one reason for a well written book to fail in the marketplace and that's lack of marketing. Nobody knows your subject or your book as well as you do, and nobody can do a more effective job marketing it than you can, so if you want to succeed at self publishing, you have to commit yourself to becoming at least as good at promoting books as writing them. If you don't have it in you, save yourself a few thousand dollars and a lot of sleepless nights, sign up with a reasonable subsidy press like Booklocker, and be satisfied with seeing your book in print.
Diet Books and Fitness Guides for Healthy Profits?
Even the most casual observer of nonfiction bestseller lists can't help but notice that diet books often dominate the list and remain there for years at a time. I believe this has been going on at least since the 1960's, may have something to do with the widespread acquisition of color televisions, but that's another story. Diet books are often branded with the name of a celebrity doctor or the latest health fad resulting from some governmental pronouncement, and are pushed strongly by their trade publishers with big budget campaigns. Fitness guides are more likely to be written by celebrity trainers, who get into the public eye by talking about the foibles of the Hollywood stars they've trained. Anybody with the ability to market a book on TV by gossiping about famous people is probably better off with a big trade publisher than self publishing, which is the subject of this blog.
As usual, I turned to Amazon for a quick look at how health oriented titles by unknown authors are selling, and I used the subsidy presses as a proxy. The reason is that none of the subsidy presses do any meaningful marketing for titles, even if they are paid to, so an Amazon Power Search turns up titles that are doing well due to the efforts of the author. The string I used was:
subject: diet or health and publisher: authorhouse or iuniverse or xlibris or booklocker or lulu
This turned up 1214 subsidy published titles in the diet, health and fitness area, of which the top 10 had sales ranks under 100,000. None of the books were in the top 10,000 during this particular check, which should set off a warning bell for the aspiring self publisher. If you were self publishing your book with print on demand and getting the majority of your non-direct sales through Amazon, which is probably true for all the titles in the list generated, you'd estimate that the current top dog is selling less than 1,000 copies a year. Even if you earned a very healthy profit margin by going through Lightning Source, Replica or Booksurge, that's hardly a living.
So, should the aspiring fitness guide self publisher give up and look into writing adult titles instead? Not at all, because the method I used above for generating the bestseller list has a serious flaw. It only includes books from authors who used a subsidy publisher, and even though some of them may be fairly savvy marketers, none of them are doing it for a living because there's no living to be had! If I was interested in self publishing diet books and health related titles myself, I would have gone through a very different exercise on Amazon, a time consuming process of elimination to search out true self publishers of related titles and look at the reasons for their success. Without doing the many hours of work, the process goes like this. Search for:
subject: diet or health
which yields 283,637 titles, a few too many for me to start looking at. Even more impressive, the first 700 or so titles on a bestseller sort were in the top 10,000, the range where a self publisher can start thinking about making a living. In fact, it's one of the most dominant categories of books I've ever seen on Amazon. On the other hand, don't forget that for the 700 or so titles in the top 10,000 there are almost 283,000 also rans.
The bottom line is that if there's a market with a seemingly infinite ability to absorb new titles, it's diet and health books. The trick, of course, is marketing. Since almost all of these titles are sold as nonfiction, whatever the truth of the matter, they make ideal candidates for Internet marketing. As our check of subsidy publishers showed us, this isn't a niche category where a book is likely to get sales just based on the title, there's just too much competition. But if you start with the website, put the draft of your book online and work to build the traffic, you'll soon get an indication of whether it's going to work for you. If you start getting regular e-mails asking when you're going to publish the book, it's time to hire an editor, some proofreaders, pick a print on demand printer and publish.
A Story of Alternate Publishing Universes
Once upon a time there was a college student named Joe Newbie who blogged every day about the college life. He wrote about the food in the cafeteria, the parties he went to, what he paid for textbooks and life in the dormitory. Several times a day Joe posted updates to Blogger, and by the time he declared as a business major, thousands of people were reading Joe’s blog every day. Joe’s friends and readers kept asking him, "When are you going to publish a book?" but Joe laughed it off until he needed a project for Entrepreneurial Thinking
Alternate Publishing Universe #1
The knocking continued, but Joe had already drifted off, and as he had written in his blog that very week, "sleeping through noisy interruption in the afternoon is a vital skill for college students." When he finally woke up just before dinner, the first thing he did was sign the contract and stuff it in the return package thoughtfully provided by the acquisitions editor, Peter Heartless, and dropped it off at the campus center to be returned to Big Trade Publishers. Over the next two months, Joe edited his last couple years of blog postings into a book titled "How to Live a Happy Life at College" and sent it off to the publisher. He didn’t hear a word for a couple months after that, then a package showed up labeled "Final Proof" with a note from Peter Heartless that they were in a real rush, so could he please identify any errors by the end of the week.
Joe looked at the contents and was stunned. A mock-up of the cover showed that the title had been changed to "Party Animal and Scholar" and there was a stock photograph that made him blush. As he scanned the pages, his fists clenched as tightly as his teeth at every stupid sidebar graphic with helpful hints that weren’t his and often directly contradicted what he’d written. When he examined the text more closely, he saw that it had been radically changed to match the hints and tips, and that his style had been completely obliterated in accordance with some politically correct guidelines. One of the reasons Joe’s blog had been such a hit was his colorful language and honest emotions. His fingers shaking, he dialed-up Peter Heartless, who didn’t even make a show of sympathy. "Read your contract," Heartless told him, "The only reason we’re showing it to you at all is because we couldn’t hold you liable for any slander otherwise. We all worked very hard on this and it’s going to press next week. We spent thousands on that cover art, you should be grateful."
Joe sunk into depression and began to lose weight. His grades at school suffered, he lost interest in posting to his blog, and the same students who came to his advance check party now bought the book just to laugh at him. Nine months later when the first royalty statement came, it showed a negative balance of $357.86. As Joe frantically read the statement, he realized that the 10% of net rate on the first 10,000 books was earning him less than $1.00 each, and they weren’t selling that well. Six months later, the next royalty statement included a check for $1854.21, and there were quite a few returns. If Joe had been around to see the following semi-annual statements, he would have seen that total royalties for the book came to less than $7000, but by that time, Joe had graduated (by the skin of his teeth) and gone to Alaska to find himself. Unfortunately, before Joe could find himself, a bear found him, and the bear lived happily ever after.
Alternate Publishing Universe #2
Joe got up and answered the door and was greeted by Lin Smart, a shy girl from his Entrepreneurial Thinking class. Lin had a whole handful of papers which she proffered to Joe, explaining that she’d done an analysis of his contract and compared it to self publishing with print on demand, which happened to be what Lin’s mother did for a living. Lin showed Joe that she had researched Big Trade Publishers titles, and based on the expected word count, that they would publish his book in a 6x9 format at 192 pages and price it at $14.95. With royalties starting at 10% of net, and net selling price averaging about half of list, Joe would be earning a little less than 75 cents per book. If the book sold more than that, his royalties could eventually climb to just over a dollar a book, but she pointed out that only two percent of books in print sell over 5,000 copies a year. She had also read the fine print in the contract and pointed out that Joe was giving up the right to make future blog posts without getting them approved first, something that hardly fit his free wheeling style, that he had no control over the editing of the book, and that he was giving up the right to write any other books, blogs or anything that could be construed to compete with the Big Trade Publishers version. Lin explained to him that Big Trade Publishers wouldn’t actually market his book, that they were just hoping to get sales from his blog readers and that they would try putting an outrageous or lurid cover on the book to attract bookstore customers. It all sounded pretty bleak.
Then Lin showed him a Lightning Source case study she’d printed off the web. She explained that Joe could get a 192 page 6x9 book printed and shipped to Amazon and Ingram, the largest book distributor in the US, for less that $3.50 each, without having to fill his dorm room with books or paying for shipping and handling. Joe could give the book a $14.95 cover price, assign a short discount of 25%, and Amazon and Ingram would pay (14.95 x 0.75) $11.21 per book, leaving Joe with a net profit per sale of over $7.50. In other words, Joe would earn ten times as much on every sale as he would with Big Trade Publishers, and not sign away any rights to his future! Since Joe’s blog was going to do all of the marketing for the book in any case, Lin estimated that Joe could still sell about 50% as many books as he would have with Big Trade Publishers without getting his book in the chain stores. So if he was willing to gamble on her judgement, he could come out five times ahead.
Joe was floored. All this time he’d thought that the pinnacle of publishing was getting published by a reputable trade, and now this wonderful young woman was telling him that her mother had quit writing for the trades in order to become a self publisher. He asked Lin how much it would cost him to become a publisher and she answered quickly, "About $250 to buy a block of ISBN numbers from Bowker, set-up costs of about $100 at Lightning Source, and the work to prepare the book and design a cover, which I’ll bet my mother will help us with." Joe enthusiastically agreed, and the two of them were inseparable over the next few months, laughing at private jokes as they edited the blog entries into a book and got their friends (and one professor) to act as proofreaders. They published the book that summer, advertised it on the blog which was now getting over 5,000 visitors a day, and by Christmas they had sold 1,500 copies, netting them over $10,000 before taxes. The next year, sales continued to grow, Joe acknowledged that Lin was the best thing that ever happened to him, and they got married. Joe wrote another book about how to be happy which became a bestseller titled "Open the Door to Lin" and they lived happily ever after.
Poetry and Memoir or Getting Published
Because the vast majority of poetry books throughout time have been self published or subsidized, only an ignoramus would think there's any shame involved. There's a reason that self publishing poetry has been so popular over the centuries - nobody was willing to pay for it. The "real" money in publishing poetry has always been in publishing dead poets Even those who had success in their lives probably earned more for their heirs after they went on to explore the great mystery. These days I'm suspicious that more money is made selling dreams of public recognition to poets than selling books of poetry. The rip-offs range from sham competitions with dubious honors as the prize to overpriced subsidy publishing deals with even more overpriced marketing that doesn't stand a poet's chance in hell of selling any books. Much of the same is true for memoir, though if you're infamous, getting published is a real possibility.
All this negativity is just the setup for my business take on self publishing poetry or memoir. It's not a business, it's not even a lottery ticket, so don't think of it that way. If you want a beautiful book you can proudly give to your family and friends, on fine paper with an embossed cover, work with your local printer and under no circumstance plan on buying more than 100 copies. You'd be surprised how hard it is to give away a hundred books, I'm speaking from experience here. If you really just want to see your poetry or memoir in print and be able to tell your ex-friends and disgusted family to buy it through Amazon or order it through their local bookstore, shop for an inexpensive subsidy press. My only warning is not to give away any rights because you never know. Prices range from free (be careful) to a few hundred dollars to get a book in print and available through distribution, I couldn't justify paying more than $500 to a subsidy publisher under any circumstance. Just comparison shop until you drop and don't get caught up in worrying about royalties because it's not a business.
The other way of getting a poem published is to sneak it into another book. The first computer book I wrote for McGraw-Hill had a poem tucked away in one of the later chapters, though I'm sure critics would have called it a limerick or a ditty. Give me a break, it's not easy to write a poem about computer hardware. The high point of my career as a poet was receiving a letter from the project editor at McGraw-Hill telling me I had to credit the poet and get a signed permission. I don't think it would be possible to hide a memoir in another book without using invisible ink, but if I do think of a way, I'll get rich selling the idea:-)
Acquisitions Editor and Publisher
Self publishing as a business requires you to fill several job functions, some of which conflict with each other. The conflict that causes some self publishers to talk to themselves out loud is the one between the author and the acquisitions editor. The publisher job function can be thought of as the executive management position. It's the publisher who hires and fires acquisitions editors based on whether or not the manuscripts they acquire end up making money for the publishing company. Being the publisher can be fun and being the author can be fun but being the acquisitions editor is essentially a bean counting job. It's not about whether you like a given book (you better like it if you wrote it) or whether or not you judge the manuscript as being well written, it's strictly a judgment call about whether the title will earn the publisher money.
In the self publishing business, you are the acquisitions editor. I usually talk about marketing as being the primary job, but unless you are one of those evil geniuses who can sell salt to salt miners, you need to start with a title that is marketable. That might sound like the author's job, but the author's job is writing a good book. It's the acquisitions editor's job to tell the author not to bother if the book doesn't have a market. As a self publisher, you are in an excellent position with your multiple personalities to save the author some heartbreak by not letting the author spend months or years writing a book that you aren't willing to acquire. Unfortunately, most new authors start on the path to self publication by writing a complete book and only look into self publishing when they can't find a trade publisher. At that stage, there's just no chance that they are going to fill the acquisitions editor job function properly and turn themselves down if there's no market.
I've already written quite a bit about doing research to establish whether or not a market exists for a given title, which is initially the job of the author and ultimately the job of the acquisitions editor. You may have done a great job focusing your knowledge and skill into writing a book specifically for a proven market only to find that you don't have any marketing talent at all. That's not a minor stumbling block, it's the whole shooting match. It's the great tragedy of self publishing that you can do everything right and still fail when it comes to selling books, and not just because it's the hardest part. The problem is that selling books is the first point in the self publishing process that actually brings you into legitimate contact with the publishing world. It doesn't matter if you hired an editor and some proofreaders who all told you the book was great, that's not real contact. So, unless you've been successful with an Internet site or some other form of publishing before getting into the book game, you just don't know if the pieces are all going to add up. And that's what the job description of "publisher" is, determining whether all the pieces will add up.
I know some self publishers who really have done everything right, who are selling some books, and who have accumulated the experience see where things are heading. They often find that they can sell books through traditional promotional methods, like book readings and radio interviews, but the number of books sold per appearance just doesn't justify the ongoing effort for them. There are books that really require broad stocking in stores to gain traction, and books that benefit from having a trade publisher. I'm not shy about saying to these self publishers, "Look, the reason you didn't break into the trades earlier was that you didn't have the understanding of the publishing business you've acquired going through the self publishing process. Self publishing hasn't worked out the way you hoped and you say can't afford to put more time into it, so give being a trade author another shot." There's one way to impress an acquisitions editor at a big publisher, that's to follow their guidelines for submissions, write a great query letter, and keep trying.
Numbers for Book Sales and Nielsen Bookscan
I've written a lot about publishing industry numbers and how to estimate title sales using Amazon sales ranks. The one program I've never had direct access to is Nielsen Bookscan, due to the price. I have seen Nielsen reports thanks to low friends in high places, but I've never systematically used Nielsen Bookscan for research as practically everybody else with an interest in publishing numbers does. Nielsen aggregates results from the biggest North American book retailers, including Amazon, Barnes & Noble and Borders, but they lack data from the mass merchandisers like Walmart and supermarkets. Bookscan results are usually given as representing about two thirds of the industry (65% to 70%), but this obviously varies by title. For bestsellers that are widely stocked in mass merchandisers, you'd expect them to be way off, but for books that are sold almost exclusively through Amazon and the chains, which represent a huge part of the trade, they should be pretty spot on.
In an Op-Ed published in the New York Times last week, Tim O'Reilly pointed out that according to Nielsen Bookscan "only 2 percent of the 1.2 million unique titles sold in 2004 had sales of more than 5,000 copies." That amounts to 24,000 titles selling more than 5,000 copies a year. To put that into context, Amazon lists over 24,000 titles published by just one giant trade, McGraw-Hill, in the last five years. Obviously, some of those books are out of print and most of the rest aren't selling over 5,000 copies a year, but it should give you an idea about the relative smallness of the pie. According to Nielsen, they log sales of over 300,000 individual titles in a typical week, but by the time you get to the end of the year, only 1,200,000 unique titles have been sold. Those 900,000 additional titles that have to get smeared out over 52 weeks can't be averaging more than a few sales a year.
If you make a dollar or two a book as the author of a moderately successful title, selling a few thousand books isn't going to change your financial life. If you make five or ten dollars a book as a publisher, you might earn a living with a few average books, or get rich with a few hundred. Years ago, before print on demand publishing added its contribution to the explosion of new titles, I worked out from various sources that the average trade published book sold 2,000 copies. If anything, I suspect that number may have gone down. Bookscan data gives acquisitions editors a quick and painless (or brainless) way to estimate the market size for a particular title. As a self publisher, if you don't go through a similar exercise using whatever data you can, you're just kidding yourself about being in the publishing business.
Another fun number that I can't credit because I haven't a clue where I first saw it, is that Barnes & Noble and Borders turn over their inventory around twice a year. Just imagine, of the 100,000 plus titles in your local superstore, a large proportion won't even sell one copy before getting returned to the publisher, another big chunk will sell at such a slow rate across the chain that they get dropped within a few months, and of the remaining books, the average title will sit on the shelf for six months. Barnes & Noble and Borders have around 1300 superstores between them that represent the majority of the retail bookstore trade, so two copies per store a year only gets you to 2,600 books for a success! If we intentionally overestimate and say that the two chains only represent half of the bookstore market and that a given book is actually stocked everywhere else (which isn't possible due to bookstore size limitations), it would give us just over the magic 5,000 number.