Electronic books continue to show explosive growth in the Association of American Publishers Monthly Sales report. The AAP reports that June 2010 gross e-books sales were $29.9 million, an increase of 118.9% over the $13.7 million in sales reported for the same period in 2009. Gross e-book sales for the first six months of calendar year 2010 are $180 million, a 203.8% increase in sales over the $59.2 million sales reported for the same calendar year date in 2009.