The PDURATION function returns the number of periods for an investment to reach a specific value at a given rate. Mathematically, PDURATION = (log(futureValue) - log (currentValue))/(log(1 + rate)).

Parts of a PDURATION function

PDURATION(rate, present_value, future_value)

PartDescription
rateRequired. The rate at which the investment grows each period.
present_valuepresent_valueRequired. The investment’s current value.
future_valuefuture_valueRequired. The investment’s desired future value.

Notes

All values must be positive and greater than 0.

Examples

PDURATIONFORMULA
1.817059493=PDURATION(0.25, 10, 15)
3.600511394=PDURATION(0.75, 2, 15)
  • RRI: The RRI function returns the interest rate needed for an investment to reach a specific value within a given number of periods.