TurboTax pogrom on 1099-DIV has a step "tell us if any of these UNCOMMON situations apply to you. (it is actually in lower case" uncommon").
I have to say that TT has been a little misleading, because it looks very "common" that "a portion of the dividends is U.S. Government".
Hence for over a decade, I just assume I had none (because TT says it is uncommon!). I have Fidelity FDRXX for over 20 years, and I knew there is a PDF file showing the percentage (FDRXX is 50% or more), but I never apply it till now. For 2020, I entered the number, and plan to file amendment for the past few years, because I had FDRXX dividend in the thousands.
