After I reported yesterday that the number of books in D.C.’s public library system had declined from 2,242,514 in 2010 to 1,466,010 in 2012, several of you wrote in to express your incredulity at the sharp drop. In fact, if you go back a little further, the decline is even steeper: In 2007, DCPL reported 3,037,696 volumes. In other words, the library system lost more than half its books over five years.

So what accounts for the drop-off? Essentially, three things: budget cuts, better accounting, and an emphasis on electronic media.

According to DCPL spokesman George Williams, DCPL’s collections budget for fiscal year 2009 was $4.27 million. For 2010, that figure was cut to $3.02 million. It stayed about constant in 2011, at $3.01 million, before dropping further to just $1.67 million in 2012. (Thanks to a one-time allocation approved by the D.C. Council and the mayor, it’s back up to $3.85 million for 2013.)

At the same time that DCPL found itself with fewer financial resources, it shifted its emphasis toward formats that were increasingly in demand. Out went some of the bulky encyclopedias that used to line so many library shelves; in came e-books, which aren’t reflected in the volume figures above. Williams emphasizes that despite the decline in volumes, circulation has gone steadily up. In fact, the circulation numbers are practically a mirror image of the volume number: Circulation went from 1,426,531 in 2007 to 3,363,313 in 2012. There are 35,000 e-books and downloadable media titles in DCPL’s collection, a figure that will continue to grow.

Finally, as part of its efforts to modernize the library system—-anchored by a series of construction and renovation projects—-DCPL also worked to update its database, “physically going through and checking to make sure that items in our catalogs were actually on shelves,” says Williams. This process picked up around 2010 as collections began to be moved from interim libraries into new and improved permanent facilities.

“You’re physically touching every book,” says Williams. “So you’re checking to see what books are still useful, what books are in really bad shape, what books are really old and need to be replaced.” That means not only deteriorating volumes, but, say, children’s books about Yugoslavia.

Williams contests the notion that the gorgeous new libraries don’t have many books in them. He says each new library has a minimum opening-day collection of 40,000 books, CDs, audiobooks, and DVDs, and a capacity of 80,000.

So what happens to all the books that are retired? Two things: Some, says Williams, are sold to Better World Books, which resells them as used books; others are simply recycled.

Library image via Shutterstock