Churchill Down's spring meet concluded with a 6-percent decline in the average number of horses running per race and a slight decrease in average daily purses.The spring meet ended on Sunday.In a statement, President Kevin Flanery blamed a "substantial" decline in the North American foal crop and regional competition from nearby tracks in states where casino gambling feeds purses. Efforts to amend Kentucky's constitution to allow casino-style gamblingfailed during this year's General Assembly session.Flanery said Churchill Downs staff is looking at ways to increase field sizes in the short September meet, the fall meet (which starts in late October) and "further down the road."Here are the recent trends in Churchill Downs' spring meet.