Hi,
Assuming you had TurboTax transfer the 2016 data to your current (2017) return, that information can be found under Wages and Income--- Investment Income ---- Capital Loss Carryover. Your 2016 loss carryover should be shown. Clicking on update will allow you to walk through the details. If the 2016 carryover wasn't transferred, then you enter the amount yourself while in the Capital Loss Carryover update window. This worked in my return.