Wagering on races held at U.S. racetracks during the first quarter this year was up 6.2 percent despite a 3.4 percent drop in the number of races held, according to figures released on Thursday by Equibase, the best three&#45;month showing for handle figures in the economically challenged racing industry for some time.Wagering during the first quarter this year was $2.63 billion, up $154 million over the 2017 first&#45;quarter number, according to the figures. Though March figures this year were greatly aided by the scheduling of the Florida Derby card during the month, the surge in wagering also coincided with predictions by many racing officials that handle would begin to increase in the first months of 2018 due to the impact of tax&#45;rule changes implemented last fall that are highly beneficial to horseplayers.Some commentators had predicted that handle could jump nearly 10 percent as a result of the changes, and the per&#45;race wagering figures for the quarter dovetailed with that forecast. For the quarter, per&#45;race wagering was $360,250, a 10.0 percent increase over the 2017 figure of $327,599.Annual handle figures for U.S. races have been stagnant for five years, with little movement as the industry grapples with increasing competition, a static fan base, and stubborn declines in field size, the foal crop, and the number of races held. But the industry has been buoyed by hundreds of millions of dollars in casino subsidies flowing annually to both racetrack operators and horsemen, leading to the highest per&#45;race purse figures in the sport&rsquo;s history even as handle remained stuck in neutral.For the quarter, purses were up 5.8 percent to $225.0 million, according to Equibase. The average purse was $30,848 per race, a record number and a 9.5 percent jump over the first&#45;quarter per&#45;race figure last year.The figures were aided by an especially strong March, which had nine weekend dates rather than eight in March last year. That led to a shift in the Florida Derby card from April last year to late March this year. The Florida Derby card generated a record handle figure of $49.9 million, aided immensely by a mandatory payout of the track&rsquo;s jackpot&#45;style Rainbow 6, which attracted $16.6 million in bets.Handle in March was $972.4 million, up nearly $100 million over the March figure last year and a jump of 11.35 percent, according to Equibase. The number of races held during the month was statistically identical to last March.Average field size during the quarter was up a minor amount, from 7.85 horses per race during the first quarter last year to 7.92 in the first quarter of this year. Still, any gain in field size is considered significant for the U.S. racing industry, which continues to face challenges in maintaining the large field sizes that gamblers prefer.The year started with massive amounts of race&#45;day cancellations in January as Northeast and Midwest tracks faced trying winter conditions. However, that led to large gains at warm&#45;weather tracks in California and Florida, as simulcast bettors searched for available signals, mitigating the impact of the decline in race cards.