Purpose
 
  
  Synopsis
 
 
 function disc(a:real, t:real)
 
 
  Arguments
 
 
 
  
   | 
     a 
     | 
     Discount factor, real number greater than -1
     | 
  
   | 
     t 
     | 
     Time, real number
     | 
 
 
  Return value
 
 
 Annual discount value:
 1/(1+a)t-1.
 
  Further information
 
 
 This function calculates the annual discount for the given period of time and discount factor.
 
 
  Module