What is CPI used for? Mostly to index the Social Security payments, and, to a lesser effect, adjust tax brackets. Retirees don't use much credit, on the contrar

What is CPI used for? Mostly to index the Social Security payments, and, to a lesser effect, adjust tax brackets. Retirees don't use much credit, on the contrary, they benefit from higher borrowing rates, because they are those that lend money. So it makes sense that borrowing costs are not included in the CPI. Otherwise it would be double-tap for retirees - they get greater SS increases and greater income from safe investments.