PHILADELPHIA — Gross revenue from slot machines at the state’s 11 casinos was down 4.4 percent last month from the same period a year ago, a decline blamed in part on the effects of Superstorm Sandy.

The Pennsylvania Gaming Control Board reported Friday that gross slots revenue at the state’s 11 casinos last month totaled $188.4 million, down from $197.2 million during the same period in 2011 — when just 10 casinos were open. The decline marked just the fourth time since the state’s first casino opened in 2006 that monthly slots revenue was down.

Sandy caused massive power outages, especially in the Philadelphia area, which has four casinos. While there was little major flooding, the storm’s heavy rains and high winds downed trees and made travel difficult in the region.

In Chester, just outside Philadelphia, Harrah’s closed its casino on Monday and part of Tuesday due to the storm, gaming board spokesman Doug Harbach said. Other casinos were not at full operation due to the storm, which wreaked havoc and hampered daily life in the region for much of the final week of October.

In hard-hit New Jersey, the effect on the casino business was much greater. Atlantic City’s casinos weren’t given the OK to reopen until Friday, five days after the approaching storm forced them to close.