Turbotax lists an effective tax rate of 19.45% for my 2022 fed return. I get 21.02% when I use their numbers and divide total tax by taxable income. Can anyone explain?

I have complicated returns that I understand pretty thoroughly.  This year I decided to file my own returns using TurboTax.  I was surprised by how well  TurboTax worked.  Then, after I filed, I caught this small discrepancy.  Should I be concerned about this -- or about TurboTax more generally?