According to Nielsen Bookscan, which tracks sales from major booksellers, only 2 percent of the 1.2 million unique titles sold in 2004 had sales of more than 5,000 copies. -- New York Times
Depressing: 2% = 24,000 titles
Really depressing: 98% = 1,176,000 titles
5,000 copies isn't exactly a raging success, either. Let's do some more math. If a novel comes out in hardcover, and sells exactly 5,000 copies (and to keep things simple, has a 5,000 copy first print run and zero returns), sales would be:
5,000 copies X $22.95 cover price = $114,750.00
Let's say the author gets 8% royalties, which would = $9,180.00. Subtract the agent's 15% cut of $1,377.00, and the author is left with $7,803.00.
Hopefully the author didn't sign for a huge advance, or quit the day job.
If a novel comes out in paperback and sells exactly 5,000 copies, things are much worse:
5,000 copies X $6.99 cover price = $34,950.00
6% royalties = $2097.00, subtract the agent's cut of $314.55, and the author is left with $1,782.45 [and if this author also signed for a $5K advance: $1,782.45 - $5,000.00 advance = ($3,217.55).]
What's ominous is Bookscan telling us that 98% of the titles in 2004 didn't even make the 5K mark.
I need an aspirin.