Rate (Interest Rate) Returns the interest rate per period of an annuity.
        
Example
                 
PV * (1 + rate ) ^ nper + pmt (1 + rate * type) * ( ( 1 + rate ) ^ nper - 1 ) / rate ) + fv = 0

             FV      =    Future Value
             PV      =    Present Value
             Rate   =    Interest Rate per period
             Nper   =    Number of periods
             type   =    Payment At (Beginning = 1 , End = 0)
             pmt   =    Payment Value

             Example

         Present Value = 20,000 Bath, Future Value = 50,000 Bath, Payment Value = 1,000 Bath Number of periods = 5 Years

         Solution
         -20,000 * ( 1 + rate ) ^ 5 + -1000 * ( 1 + rate * 0 ) * ( ( ( 1 + rate ) ^ 5 - 1) / rate ) + 50,000 = 0
         rate = 0.16567 , 16.57 %          Read more »