The storm forced the city's 11 casinos to close for three days, causing millions of dollars in losses during what would have been one of the busiest weekends of the year.
The state Division of Gaming Enforcement reports the August revenue numbers were down 19.8 %. The previous record was set in March 2009, which saw a 19.4 % decline. Also hurting things was the fact that there was one fewer Sunday this August compared with last August.
The casinos' take from slot machines fell nearly 21 % while table games revenue decreased by 17 %.