Tax amount is wrong when pro-rating

ITEM 1 $87.75 for now until 02/01/2019 - 00:00, then $94.02 per month
SETUP $51.28 for now until 02/01/2019 - 00:00, then $51.28 per month
Subtotal: $139.03 for now until 02/01/2019 - 00:00, then $94.02 per month
Taxes & Fees $32.35 for now until 02/01/2019 - 00:00, then $24.70 per month
Total: $162.67 for now until 02/01/2019 - 00:00, then $110.00 per month

The values listed beside "Taxes and Fees" are wrong... 139.03 + 32.35 is NOT 162.67, and 94.02 + 24.70 is NOT 110.

I have the tax rate set at 17% - doing the math manually suggests ITEM 1, SETUP, Subtotal and Total are all correct; and 139.03 * 1.17 is indeed 162.67.