According to Fowler (2016), "Congress added the ACE adjustment in an attempt to bring the AMT tax base close to a corporation's economic income." He goes on a few lines down to say about the rules for determining ACE where it states, "Any expenses or losses deductible for preadjustment AMTI purposes but not deductible for E&P are not deductible for ACE purposes (e.g., 70% DRD)." Now, the one item that is getting me confused is in the section that states, "the 80% and 100% DRD and the U.S. production activities deductions are exceptions to this rule. These two deductions are allowed for ACE purposes ever though they are not deductible for E&P." Yet, Fowler states earlier, "Under the American Recovery and Reinvestment Act of 2009, interest on tax-exempt bonds issued in 2009 or 2010 is not treated as and Adjustment for ACE purposes." So, what happens to the other years of the tax-exempt bonds interest if the DRD is an exception and able to be deducted.