Indiana casino revenue fell 3.5 percent through the first eight months of the year, a steep decline compared with 6-percent overall growth at U.S. casinos during the period.

The American Gaming Association said this week that U.S. casino revenue increased to $23.8 billion through August, led by a whopping 705-percent increase in Kansas, where a casino opened in February overlooking Kansas Speedway in Kansas City.

Revenue from the Indiana’s 13 casinos fell to $1.8 billion.

A casino that opened last year in suburban Chicago coupled with the addition of a casino at a horse-racing track south of Columbus, Ohio, likely cut into Indiana casino revenue, said Ed Feigenbaum, who publishes the Indiana Gaming Insight newsletter.

“Nobody expected it; nobody was prepared for it,” he said of the impact the Columbus casino has had on Indiana.

And it’s only going to get worse, warned Ernest Yelton, executive director of the Indiana Gaming Commission. That’s because another casino in Columbus opens this month, followed by one in Cincinnati slated to open in February.

The new competition combined with a sluggish economy creates a recipe for concern, he said.

“This is just a slight preview of what we can expect when the one in Cincinnati opens,” Yelton said. “It will have a direct impact, particularly on the three [casinos] down in southeastern Indiana.”

In August, the last month for which statistics are available, Indiana’s casino revenue grew less than 1 percent, to $222.6 million, commission statistics show.

The largest decline in Indiana came in July, when revenue from the 13 casinos fell nearly 9 percent.

Still, Indiana’s $1.8 billion in casino revenue through August ranks as the fourth largest in the country, trailing only that of Nevada, New Jersey and New York.

Through August, tax money Indiana collected from the casinos also was down, by 5 percent, to $426.9 million, according to the state’s gaming commission.

All but four of 23 states with casinos reported higher year-to-date revenue, the American Gaming Association said. Delaware, Missouri and New Jersey also reported declines.

The data exclude results from casinos owned by American Indiana tribes.

In the Indianapolis area, Hoosier Park's casino in Anderson reported $128.4 million in revenue through August and Indiana Grand Casino in Shelbyville reported $141.7 million.