June e-book sales are in, at $80.2M, which is a little below May’s $87.7M figure. Overall, sales so far in 2011 have been somewhat up and down, but each month has been consistently well above even the best month of 2010 (December’s $49.5M).

Monthly e-book sales. June 2011: $80.2M

To recap, the last 13 months of e-book sales data:

• June 2010: $29.8 M
• July 2010: $40.8 M
• Aug 2010: $39.0 M
• Sep 2010: $39.9 M
• Oct 2010: $40.7 M
• Nov 2010: $46.6 M
• Dec 2010: $49.5 M
• Jan 2011: $69.9 M
• Feb 2011: $90.3 M
• Mar 2011: $69.0 M
• Apr 2011: $72.8 M
• May 2011: $87.7 M
• June 2011: $80.2 M

Quarterly e-book sales. Q2 2011: $240.7M

For the quarter, e-book sales came in at nearly a quarter of a billion dollars, at $240.7M. After last quarter’s $229.2M, e-books are not quite on pace to hit a billion dollars for the year. (Publisher’s Weekly says first-half 2011 sales total $473.8M, which is a little higher than adding all their monthly totals; they seem to add in some late-reporting sales or something.)

Sadly, PW also seems to have stopped providing as much detail on breaking down print book sales (hardcovers, trade paperbacks, etc.), although they did reveal that print book sales “plunged” in June, with trade paperback sales down a whopping 64%, adult hardcovers down 25%, and mass-market paperbacks down 22%. Certainly the closing of Borders stores has not been kind to print book sales. While they didn’t provide breakdowns, with those steep declines it’s hard to see any print categories beating out e-book sales in June.

UPDATE: Based on my comparisons to last year’s figures, we can safely estimate that even the largest print category (adult hardcover at roughly $55.6M) was well under e-book sales for the month. I’ve also dug up some 6-month figures for the first half of 2011; print books (all 5 trade categories) combined to total $1,672.2M for the year (compared to $473.8M for e-books), which means that e-books accounted for a record 26.9% of all print/e-book sales for the month, and averaged 22.1% for the first half of 2011.