The dramatic drop-off in betting on Thoroughbred racing did not let up in July, with total betting on U.S. races plunging 13.4 percent compared to July of 2008, according to figures released by Equibase on Wednesday. Betting on U.S. races fell from $1.21 billion in July last year to $1.05 billion in July this year, according to the figures. Through the first seven months of the years, betting has now declined 10.9 percent compared to the first seven months of last year. In June, betting was down 16.9 percent. Purse distribution during the month was down 7.4 percent, according to the figures, from $119 million in July of last year to $110 million in July this year. Purses have been more resilient than handle because a significant portion of purse revenues are derived from subsidies from slot machines. For the month, total race days in the U.S. dropped from 660 to 651, a decline of 1.36 percent. Also this year both Del Mar and Saratoga, the highest-handling summer tracks, started their meets a week later, which means that figures from last July would have been bolstered by the extra days.