(Harrisburg) -- Annual revenue from Pennsylvania slot machines has dipped for the first time since the state's first casino opened in 2006, reflecting increased competition from border states.

The Gaming Control Board released revenue figures for calendar year 2013 on Friday. They show that gross revenue from Pennsylvania's slot machines dipped 3.5 percent to less than $2.4 billion. The state collected nearly $1.3 billion in taxes from slot-machine play.

Pennsylvania had seen six consecutive years of revenue gains.

Table games, which were introduced in 2010, are still showing strong growth. Gaming regulators will release annual revenues from table games later this month.