# Immediate / Ordinary Annuity Interest Rate Calculator

[insert_php]if(isset($_POST[‘submit’])){

$P = $_POST[‘value1’];

$N = $_POST[‘value2’];

$I1 = $_POST[‘value3’];

$I=$I1/100;

$A=(1+$I);

$A1=pow($A,-$N);

$ImmediateAnnuity = $P*$I/ ( 1 – $A1);

//forrmula Immediate Annuity = pi / ( 1 – ( 1 + i )-n )

//p = Sum to invest,

//n = Time period(in years),

//i = Annual rate of return.

echo”Result is : $ImmediateAnnuity”;

}

## Example of of Immediate / Ordinary Annuity Interest Rate Calculator

Suppose that p is 5, i is 8 and n is 3, then

Immediate Annuity = pi / ( 1 – ( 1 + i )-n ) = 5 / (1 – (1 + i) – n) = 1.940