We have a 4% annual rate compounded quarterly, which is 1% per quarter. We are solving for a future value, so we use the future value of annuity formula (I'm assuming payments are made at the end of the period, rather than at the beginning of the period). We look under the 1% column for 16 periods, and get a factor of 17.25786. We divide the $65,000 future value needed by 17.25786 and get $3,766.3998, or rounded to the nearest penny, $3,766.40. So we would need to make quarterly payments of $3,766.40 compounded quarterly with an annual rate of 4% for 16 periods to have $65,000 at the end of 4 years.