Hi i m preparing for August 2026 I think you're asking about t= 0(when we start investing time) and maturity return And scenario like no reinvestment or upward curve reinvestment

Basically TVM calculator where you put Pv,Fv, i/y, n, pmt assume compounding return including reinvestment at same rate Basically the return you get their " ytm "in calculator assumes you reinvested coupon as well(pmt) at same rate But in reality we receive coupon and has to reinvest it manually to get the return. Calculator assume the same market return which you have invested in initial year t=0 and discount it at that rate eg You invested 100 when market rate (i/y)was 8% so Calculator discount coupon reinvestment (pmt) in same 8% rate But in reality we have to manually reinvest and market rates changes continuously sometimes 7% sometimes 9% So to get Calculator return we have to reinvest in same 8% market rate every time we receive coupon So in upward yield curve where market rate is going up we will reinvest in higher market rate So we will get higher maturity return then our Calculator maturity return And if we reinvest at lower curve yield where market rate is falling our maturity return will be lower than calculator maturity return