A government audit has found the Bush administration allowed insurance companies to hold onto tens of millions of dollars that should have gone to Medicare consumers. The Government Accountability Office says the companies kept the money because the administration failed to perform mandatory audits and recover wrongly paid funds. The money could have been used to either reduce payments or provide more benefits to senior citizens. The proportion of audited Medicare companies fell to 14 percent from 24 percent in 2001. The Bush administration has pushed corporate involvement in Medicare and encouraged beneficiaries to enroll in private plans.