I'm working through a potential underpayment penalty on the 2021 Mac Desktop version. I'm trying to enter my withholdings by quarter. It says that the total withholdings must match a certain figure that is shown in Form 2210 line 6. It says not to estimate. However, this 2210 line 6 figure does not match my W-2 withholdings. I don't know where that number comes from, so I don't know how to match up my quarterly withholdings.
