Solved
Even if I divide by my Total Income from line 7b of my return (which is obviously wrong but the largest number anywhere in my return), I get 20.4%. (The numerator for all of the above is line 16, Total Tax.)
TurboTax divides your total tax from line 12b, by your total income, line 7b, to get the effective tax rate.
This figure is just informational, it does not appear on your tax return or affect the amount of tax that you pay.
Enter your E-mail address. We'll send you an e-mail with instructions to reset your password.