Reaching an agreement on how to balance the budget within seven years won't be easy, says Carney, in part because the Clinton and GOP budget proposals are based on different assumptions about U.S. economic performance. While the GOP plan draws on relatively conservative estimates from the Congressional Budget Office, Clinton uses more optimistic projections from the Office of Management and Budget that show greater tax revenue from economic growth offsetting the need for some cuts. "Clinton is not going to sign anything that agrees to the CBO numbers because he would be bound to them," Carney notes. "What he may do is to decide to take somebody else's numbers, either a combination of CBO and OMB numbers or some neutral economic assumptions done by third party economists. But if Clinton does this, then he will be faced with the difficult task of rejecting a Republican budget, filled with deep cuts in a number of programs Medicare and education, after he's agreed to balance the budget in seven years."