BOULDER, Colo. – U of C Federal Credit Union has begun offering a "mile high rate" of 5.280% on its 60 month jumbo certificates of deposit, making it the highest in Colorado and "a very attractive rate nationwide," according to Bankrate Inc., the North Palm Beach, Fla. rating firm. U of C FCU said it was promoting the 5.280% rate on its $10,000 CDs "to do something special for consumers to lift their spirits and encourage savings in this slow economic environment." Colorado for months has remained in a deep economic slump hurt by sharp cutbacks by telecom, dot.com and some energy firms. Bankrate said its most recent national average shows the highest yield on the jumbos at 4.8%, "but keep in mind that is only for firms offering CDs on a national scale and doesn't track all local offerings," said Greg McBride, senior financial analyst. Peggy Anderson, chief financial officer of the $640 million U of C FCU, said the 5.280% rate went into effect July 19 and "consumers will have the chance to capture this rate but only for a limited time" adding the rate promotion was launched "to help consumers get a jump start on the economy." A spokeswoman said the promotion was created "to attract deposits at a time when we are seeing high loan demand." She declined to reveal how long the "limited offer" might last except to meet unstated goals. .McBride of Bankrate said the trend on these rates "has been definitely upward" in recent weeks. U of C said it would be offering "other great rates for other certificate amounts with terms from 12 months to 60 months."