In February of 2012, President Obama released a proposal to cut the corporate tax rate by 20 percent—bringing the current corporate rate down from 35 percent to 28 percent (and to 25 percent for manufacturers). But according to Robert Pozen, a senior fellow at the liberal-leaning Brookings Institution, President Obama won’t say how he will pay for his $1.3 trillion dollar corporate tax reform plan.

Obama says his plan is revenue neutral. He promises to make up for the lost revenue from the rate reduction by closing loopholes in the corporate tax code. But Pozen points out that Obama’s corporate tax “framework” only specifically names a handful of loopholes that would pay for only 10 percent of $1.3 trillion cut and then lays out a “menu of options” to pay for the rest: