By Jack MoneyBusiness writerjmoney@oklahoman.comA record breaking number of Oklahomans and people across the nation filed initial claims for unemployment insurance last week.In Oklahoma, 17,720 people filed claims during the week, up more than 15,800 from the week prior, according to data issued Thursday morning by the U.S. Department of Labor.Across the nation, meanwhile, nearly 3.3 million workers sought initial assistance.The jump reflected an increase of 3 million, or more than 1,000%, nationally.The Labor Department stated in its Thursday release the data, which covered the week ending March 21, reflects the largest number of initial claims it has recorded since it began keeping seasonally adjusted records.Before this past week, the largest number of initial claims ever recorded was 695,000 in October 1982.The national amount far surpassed what many analysts predicted, and in fact nearly doubled some estimates.The U.S.