This is no longer an issue.
TurboTax was not printing anything for DC returns so all that could be seen was the total in the Forms tab in TT for DC Schedule I Calc.B line 1.
The derivation was established from Federal 1099-DIV forms for each payer - even though this is INTEREST on US obligations. The Federal 1099-DIV detail was in the Federal return which TT is printing.
Also, the Vanguard 1099-DIV did not print the US Gov interest values, just total dividends and elsewhere in the 1099 it gave the US Govt obligation PERCENTAGE - but did NOT calculate and show the resultant total US Govt INTEREST which is part of the 1099-DIV total. Why does Vanguard not print the result of this calculation in their 1099?
This all seems unnecessarily complicated and unhelpful for the hapless taxpayer trying to verify the details of a tax return.
