NEW YORK, Feb 3 (Reuters) - Puerto Rico's governor, battling to keep the Caribbean island's bonds from being labeled junk by Wall Street ratings agencies, will roll out a balanced budget plan for fiscal 2015, a year ahead of schedule, a top aide said on Monday. Gov. Alejandro Garcia Padilla will present a balanced budget in coming weeks, according to Ingrid Vila Biaggi, the governor's chief of staff. The governor had earlier pledged a balanced budget for fiscal 2016. Since taking office a year ago, the Garcia Padilla administration has raised taxes, overhauled retirement programs and pledged to end years of operating deficits aggravated by Puerto Rico's shrinking economy and population. A big issuer of municipal bonds, with about $70 billion of debt outstanding, Puerto Rico is rated barely investment grade by the top three U.S. credit agencies. All have said they may cut the island's credit ratings, which would raise borrowing costs and hurt demand for the island's outstanding bonds. Puerto Rico officials said in a news release that pension changes, tax hikes and other reforms helped make a balanced budget possible. They also said a projected deficit for fiscal 2014 ending June 30 would be reduced by $170 million to $650 million. "To balance the budget, we will not need to utilize contingent reserves and additional expenses that were factored into the current budget" said Carlos Rivas, director of the Puerto Rico Office of Management and Budget. Some agency operating budgets had been changed with an eye to cutting costs, Rivas said, adding the shifts and savings did not require job cuts on an island with a 15.4 percent unemployment rate. "I do think it would be positive for investors and rating agencies," Janney Capital Markets analysts Alan Schankel said. "I suspect it would have to involve some expense reductions." Prices of some Puerto Rico bonds rose on Monday, adding to bounce back gains in January from a sustained selloff that began in September. A 2042 revenue bond with a 6 percent coupon from the island's sales-tax authority rose to 77.75 cents on the dollar after closing on Friday at 75.6 cents; its spread over a comparable U.S. Treasury narrowed to 416 basis points from 440, according to Municipal Market Data. Separately, Puerto Rico Treasury Secretary Melba Acosta Febo said final general fund net revenues of the General Fund for December totaled $925 million, or $12 million higher than the preliminary figure announced in early January. The December revenues were up $203 million, or 28 percent, over December 2012, she said in a news release.