So exactly what does it mean that luxury-tax revenue continues to increase as gambling revenue continues to decline in Atlantic City?

More visitors coming to the resort? People staying longer and spending more? The effect of having more attractions other than gambling in the city?

The answer isn't entirely clear. But Atlantic City has a revenue figure trending upward - and we'll take it, whatever the reason.

Atlantic City's luxury tax is somewhat obscure. Few notice it. Few complain about it. The tax is 3 percent on alcoholic beverages sold by the glass, and 9 percent on hotel rooms, show tickets and the rental of beach chairs and Boardwalk rolling chairs.

The money is used primarily to pay off construction bonds on the Atlantic City Convention Center and Boardwalk Hall and to offset operating losses at both of those facilities.

And in 2012, luxury-tax revenue hit an all-time high of $35.5 million - a 13 percent annual increase in the midst of a seven-year decline in casino revenue.

Luxury-tax revenue is also up overall for the first four months of 2013, with nearly another 13 percent increase in April - a month when casino revenue declined 12 percent from April 2012.

So what gives?

Well, allow us to set aside, for a moment, the pervasive pessimism that seems to surround Atlantic City's fortunes these days and offer this suggestion:

Maybe it's all working.

Maybe a new restaurant here, a new nightclub there, the Atlantic City Alliance's marketing campaign, a refurbished and bustling Steel Pier, and the overall improvement in how Atlantic City looks thanks to the Casino Reinvestment Development Authority (the constant critics are particularly wrong about the Boardwalk - it is cleaner than it has ever been) - maybe that's all approaching critical mass.

No, not in gaming revenue. But we sure wouldn't be the first to note that nongambling revenue pulled Las Vegas out of a slump. And maybe - just maybe - that is beginning to happen here.

And the newest developments aren't even reflected in the April luxury-tax figures.

Just two examples: Jimmy Buffett's new Margaritaville-themed restaurant, cafe, bar and casino expansion at Resorts Casino Hotel, which opened Memorial Day weekend, has enlivened that end of the Boardwalk. At the other end of the 'walk, the Tropicana Casino and Resort opened six new restaurants this month, with Chickie's & Pete's and Tony Luke's (two Philadelphia legends) transforming the Trop's Boardwalk frontage.

Yes, it's easy (or easier) to be optimistic in Atlantic City in July, as opposed to January.

But there is no denying that there is a new excitement on the Boardwalk and elsewhere. And those luxury-tax figures are no lie. They must mean something.