WARREN — Ohio’s four casinos combined lost nearly a quarter of their revenue in 2020 compared to the previous year, revealing the tremendous impact the viral outbreak had on the state’s gaming industry.

The latest report from the Ohio Casino Control Commission shows 2020 revenue was $643.3 million, down 24.3 percent from 2019, when the casinos brought in $850.9 million.

The pandemic that struck in March caused the casinos — Jack Cleveland Casino, Hard Rock Cincinnati Casino, Hollywood Toledo Casino and Hollywood Columbus Casino — to close March 13 to June 18. The first full month they were open in the summer, July, the casinos set an all-time revenue record of $86 million.

Revenue fell to $77.3 million in August and $71.8 million in September before climbing a bit to $74.7 million in October, but as the pandemic surged, the state put into place a 10 p.m. curfew. In response, the casinos cut back their hours and revenue plummeted, settling at about $59.5 million for the final two months of the year.

Table games generated $190.7 million and slots, $452.6 million in 2020. Those numbers are way down from 2019, when table games generated $270.7 million and slots, $580.2 million. The decreases equal 29.5 percent and 21.9 percent, respectively.

For December, casino revenue was $59.8 million, a modest 0.6 percent gain from November but 19.5 percent less than December 2019, which notched $74.4 million.

Last month, table games generated $15.8 million, down 10.8 percent from November, and slots, $44 million, up 5.5 percent from the prior month.

In December 2019, table games generated $23 million and slots, $51.4 million, according to the commission.