Harper's Index and Publishing

Based on a post on Boing Boing today, I went over to the Harper's Index webpage" and input the search term "publishing".

Here are a few of the facts on publishing that have appeared in the Index over the years:

Number of science books published in the United States in 1972: 16,923.
In 1982: 7,900 (August, 1984)

Number of book publishers in the United States in 1972: 1,205
In 1982: 2,001 (March 1985)

The number of titles published in 2006, according to Bowker: 291,920

Number of books published last year in Iceland and the United States, respectively, per 100,000 residents: 212, 63 (June, 2005)