Fair Grounds will boost overnight purses 5 percent across the board beginning with Thursday’s card, the track announced Friday. Stakes purses, many of which were trimmed during the 2009-2010 meeting, will remain at current levels. Fair Grounds suffered steep handle declines last season, and structured its purse payments conservatively for this meet. Fair Grounds, as per Churchill Downs Inc. policy, doesn’t publicize handle figures, but Eric Halstrom, general manager and vice president for racing, said business is up this season. “Our handle is up markedly thus far in the meet,” Halstrom said. “We hoped this would be the case, and we’re pleased to be able to raise purses.”