Excluding U.S. obligations portion of Capital Gains from Maryland taxes

I'm using TurboTax 2019 Premier desktop for Windows.  In preparing my Maryland state return, I'm at the section entitled "Capital Gains From U.S. Obligations are Tax Free -- You can exclude capital gains from U.S. obligations because Maryland does not tax them.  Enter any portion of your capital gains that came from U.S. obligations."  It then lists my total capital gains (total of box 2a, total capital gain distribution, for all funds).  Then there is a single box for entering "Total From U.S. Obligations."  On my T. Rowe Price 1099-DIV, there is a table which lists interest on direct U.S. government securities.  It has a column titled "% of dividends from U.S. government securities."  But notice it says dividends.  The instructions for that column say it's for computing the amount of DIVIDENDS that are U.S. government securities, and it's multiplied by box 1a which is total ordinary dividends, not capital gains.  So I can't use that column for capital gains.  The table also has a column titled "% of fund in U.S. government securities at December 31, 2019."  But the instructions for that column say it's for computing an exemption from state intangible property tax, NOT for capital gains.  So I can't use that column for capital gains.  There doesn't seem to be a column for computing the exclusion of capital gains from U.S. obligations from state taxes.

 

Please note, this is NOT the same thing as when entering dividends for the federal return.  This is for excluding the portion of Capital Gains attributable to U.S. obligations when entering info for my Maryland state return.

 

Can anyone tell me how I can compute the portion of capital gains from U.S. obligations?  Thanks.