To approach this using Excel functions, we can use the PV (present value) and PMT (payment) functions to calculate the amount of the first deposit. Here are the steps:
1. Calculate the future value of the $1 million using the FV (future value) function:
=FV(8%, 25, 0, -1000000)
This returns a value of $4,660,962.91, which is the amount that will accumulate in 25 years at 8% interest.
2. Calculate the present value of the future amount using the PV function:
=PV(8%-3%, 25, -1*FV(8%, 25, 0, -1000000), 0, 1)
This returns a value of $1,257,407.11, which is the amount that needs to be deposited today to accumulate to $4,660,962.91 in 25 years at 8% interest with 3% annual raises.
3. Calculate the payment amount using the PMT function:
=PMT(8%, 25, -1*PV(8%-3%, 25, 0, 1257407.11, 1), 0, 1)*(1+3%)
This returns a value of $68,527.78, which is the amount of the first deposit.
So, the first deposit should be $68,527.78 to accumulate $1 million in 25 years with 8% interest, 3% annual raises, and 3% increase in deposit each year.