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**PRERATE**(//presentvalue,periods,payment,futurevalue//)

| **PRERATE** | Computes the periodic interest rate required to reach a targeted future value. |
| //presentvalue// | A numeric constant or variable containing the present value of the investment. |
| //periods// | A numeric constant or variable containing the number of periods in which a cash flow occurred. |
| //payment// | A numeric constant or variable containing the periodic payment amount. |
| //futurevalue// | A numeric constant or variable containing the amount of the desired or targeted future value of the investment. |

**PRERATE **determines the periodic interest rate required to reach a desired amount (//futurevalue//) based upon a starting amount (//presentvalue//), the total number of periods (//periods//), and a payment amount (//payment//). If payments occur at the end of each period then use the RATE function, which calculates interest accordingly.

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If the present value is less than the future value (annuities), payments are positive, and conversely, if the present value is greater than the future value (loans), payments are negative.

**Return Data Type:**     DECIMAL

**Internal Formulas:**

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The PRERATE function performs binary search iterations to home in on the interest rate value. If more than 50 such iterations are required, RATE returns a value of zero.

**Example:**

**  IF TimeOfPayment = 'Beginning of Periods'**

**   AnnualRate = PRERATE(PresentValue,TotalPeriods,Payment,FutureValue)**

**   AnnualRate *= (PeriodsPerYear * 100)**

**  ELSE**

**   AnnualRate = RATE(PresentValue,TotalPeriods,Payment,FutureValue)**

**   AnnualRate *= (PeriodsPerYear * 100)**

**  END**