Entering amount in box 42 on the T3 form (Return of Capital) and adjusting the ACB of REIT units by the return of capital amount. Is this correct.

I am entering box 42 on the T3 form (Return of Capital) but not sure what TurboTax does with this information.  When selling REIT units I am adjusting the ACB by the return of capital amount.  I would like to ensure that the Return of Capital is not being double counted.  What does TurboTax do with the amount entered in box 42 on the T3?  I assume that it is for reference purposes only.