Oil revenue from the government-owned petroleum company financed the US$12 million facility, home to the Chihuahua Dorados. The largest of five stadiums built in this baseball-crazy northern state since 2002, it boasts luxury boxes, roomy seats and space for 20,000 fans.

But not everyone is happy with this field of dreams.

"It´s too big," said longtime fan Rafael Sánchez at a game last summer that drew just a few thousand spectators. "They should have used the money to build a hospital."

Lofty oil prices have showered Mexico´s treasury with a tax windfall in recent years. Last year, revenue from the nation´s crude exports reached an all-time high of US$34.7 billion, a 23 percent increase over 2005. The bonanza has spurred economic growth and helped the nation expand anti-poverty programs and boost essential services to its citizens.

QUESTIONABLE SPENDING

It also has financed pricey gimcracks such as sports arenas and government buildings as part of the kind of spending binge not seen in decades. Public spending in Mexico nearly doubled between 2000 and 2006, vexing experts who have warned the nation to save more for a rainy day that may be fast approaching.

Mexico´s heavy crude, which fetches less than the benchmark West Texas Intermediate, has plunged 31 percent since it hit an all-time US$64.85 in August. For Mexico, the world´s No. 5 oil producer, it is sobering math. The nation relies on petroleum revenue to fund more than one-third of public spending, and now production at its main oil field is declining precipitously.

But that hasn´t stopped Mexico from burning through its recent oil jackpot like a spendthrift lottery winner. Petroleum sales and oil-related taxes have generated more than US$335 billion over the past six years. Officials used some of the wealth to pay off foreign debt and funnel a bit of cash into a stabilization fund, which contained just more than US$1.6 billion at the end of September, the latest figure available.

That´s a pittance compared with Norway, which has a fraction of Mexico´s population. The Scandinavian nation and world´s No. 8 oil producer has socked away more than US$240 billion of petroleum revenue into a fund earmarked for pension benefits for its citizens.

Petroleum revenue in Mexico has funded universities, built highways and provided health care to millions. But it also has paid for a giant flagpole in Nuevo León, remodeled churches in Yucatán and bankrolled swanky government offices in Oaxaca.

"We´ve spent this lottery money in an absurd manner," Mexico City political analyst Sergio Sarmiento said in a recent newspaper column.

LACKING TRANSPARENCY

The distribution of more than US$40 billion of so-called "excedente," or surplus revenue that exceeded the government´s forecasts, is so lacking in transparency that a prominent congressman recently called on treasury officials for a full accounting.

Legislators "don´t know, much less the citizens, really where it went," Moisés Alcalde, a member of the conservative National Action Party (PAN), said in an interview with newspaper Reforma. "No one knows how it has been applied."

Mexico finds itself dangerously reliant on a volatile commodity to fund everything from Army boots to X-ray machines.

In the first 11 months of 2006, the government siphoned US$53 billion, or 73 percent of Pemex´s revenue, to pay its bills. This has left little money for the company to reinvest in the operation and search out new sources of oil.

Production at Mexico´s principal oil field is falling rapidly with nothing on the horizon to replace it. Output at the aging Cantarell field was down more than 17 percent through the first 11 months of 2006.

"Oil is a finite resource ... yet the spending has grown tremendously," said Rocío Moreno, a researcher at the independent Mexico City think-tank Fundar. "Mexico´s fiscal situation is very precarious."

Some officials appear to recognize Mexico´s vulnerability. President Felipe Calderón has vowed to broaden the tax base and reduce reliance on crude. Federal lawmakers last year passed legislation to commit more oil revenue to the stabilization fund and to lighten Pemex´s tax burden to free up more funds for exploration.

Still, when they needed to plug a hole in the 2007 budget, lawmakers returned to the same well. Legislators rejected a proposal to raise taxes on soda makers after lobbying from soft-drink bottlers. They opted instead to slash Pemex´s budget and to raid the oil fund to boost spending on infrastructure.

"Mexico is addicted to oil revenue," said Alfredo Coutiño, Latin America economist with Moody´s Economy.com, who said the nation must find other sources of revenue or cut spending if crude production and prices keep falling. "The hangover is coming."