New Jersey saw the largest declines in gross gaming and tax revenues among the 22 states in which commercial casinos operated in 2012.

Philadelphia remained the No. 1 racetrack-gaming market in the country last year, with $835.3 million in gross gaming revenue generated, led by Parx in Bensalem for the third consecutive year.

And increasingly, patrons between ages 21 and 35 are frequenting casinos - about 39 percent of those surveyed for the first time - visiting nongambling amenities such as nightclubs and restaurants.

Those were among the key findings of the 2013 State of the States survey released Monday by the American Gaming Association, a Washington-based trade group.

Overall, the U.S. commercial casino industry grossed $37.34 billion in revenue last year, up 4.8 percent from 2011, marking the third straight year of growth, the survey's results showed. It was the industry's second highest level since 2007, before the recession hit.

"That's tremendously good news," outgoing association president and chief executive Frank Fahrenkopf Jr. said in a conference call with reporters. "You add the impact of casino tax revenues and jobs, [and] both the present and future look bright for the industry."

Fifteen of the 22 states with casinos operating in 2011 saw gross gaming revenues increase last year, the report said. Last summer, Ohio became the 23d state to open commercial (non-tribal) casinos; other states, including Maryland, New York, and Maine, saw expansion of gaming.

New Jersey experienced the largest decline in gross gaming revenue and tax revenue, Fahrenkopf said, down 8.0 percent and 8.2 percent in the wake of Hurricane Sandy, which forced casinos to close, then kept tourists away.

Meanwhile, Pennsylvania overtook Atlantic City in gross gaming revenue for the first time. The 11 casinos statewide brought in $3.2 billion, compared with $3.1 billion among the 12 Shore venues.

"Pennsylvania has been one of the great successes in our industry," Fahrenkopf said. "As Caesars Entertainment's CEO Gary Loveman said, the Northeast is an underserved market, and the numbers in Pennsylvania indeed show that's the case.

"But, of course, there is a price for that, and I think Atlantic City has been hit by that," he said. "Those that live in Philadelphia no longer have to drive to Atlantic City."

On the East Coast, New York is looking into adding nontribal casinos, Maryland is adding casinos, and MGM Resorts International is looking to build one in Washington. Fahrenkopf predicted increased competition in the next few years.

Rivals surrounding Atlantic City had an impact on the year-old Revel, which is in bankruptcy court.

"There's no question it opened in a very challenging environment and an area with tremendous competition," he said. "Expectations were high, but I think it would be wrong to call it a failure. Revel added 2,000 jobs last year in a place that really needed it."

That contributed to most of the 5.8 percent increase in casino jobs in New Jersey last year, to 34,726. By contrast, Pennsylvania's casinos employed 10,162 workers, up 2.7 percent.

The gaming association's 15th annual report was the first to survey 300 people ages 21 to 35 who had visited a casino in the last year. This group had the highest rate of casino visitation, nearly two out of five, or 39 percent - higher than the 34 percent rate of the general adult population.

Younger patrons also played the lottery and poker and wagered online more than the general casino population, the report said. Three states - Nevada, Delaware and New Jersey - have legalized some form of Internet gaming.

Younger casino-goers surveyed also were more likely to take in nongaming attractions while at a casino, such as shopping, concerts, nightclubs, pools and spas - attractions Las Vegas and Atlantic City are investing in and marketing.

"That all bodes well for the future," Fahrenkopf said. "They are our lifeblood."

Nationally, the industry employed 332,000 people in 2012, a decline of 0.9 percent from 2011, and generated $13.2 billion in wages, benefits and tips.

Contact Suzette Parmley at 215-854-2855, sparmley@phillynews.com, or on Twitter @SuzParmley.