Atlantic City casinos saw gaming revenue slip in April after posting a modest year-on-year gain in March.

AC’s computations have grown increasingly slide-rule-worthy, given the closure of four casinos in 2014 and the launch of New Jersey’s regulated online gambling market, which generated $12.7m in revenue last month.

On a pure apples to apples comparison of brick-and-mortar gaming revenue, the eight surviving casinos generated $186.3m in April, down 4.1% from what those same eight earned in April 2014. Factor in contributions from online gambling and the decline shrinks to 3%. Factor in both online gambling and those shuttered four casinos and the decline rises to 15.6%.

In pure brick-and-mortar terms, the month was evenly divided between winners and losers. The Borgata retained its death grip on the number one ranking, despite falling 2.9% to $53.5m. Runner-up Harrah’s enjoyed a 17.7% gain, but was well off the pace with $29.4m.