EXAMPLE 1.4 Rate of Return and Rate of Return


Stereophonics, Inc., plans to borrow $20,000 from a bank for 1 year at 9% interest for new recording equipment. (  a ) Compute the interest and the total amount due after 1 year. (  b )  Construct a column graph that shows the original loan amount and total amount due after 1 year used to compute the loan interest rate of 9% per year.

Solution 

 (a)    Compute the total interest accrued by solving Equation [1.2] for interest accrued.

  Interest = $20,000(0.09) =  $1800  
 
The total amount due is the sum of principal and interest.

 Total  due = $20,000 + 1800 =  $21,800   

(b)     Figure 1–3  shows the values used in Equation [1.2]: $1800 interest, $20,000 original loan principal, 1-year interest period.  

  Figure 1–3
Values used to compute an interest rate of 9% per year. Example 1.4.


    
Comment

 Note that in part (  a ), the total amount due may also be computed as

  Total  due = principal(1 + interest rate) = $20,000(1.09) = $21,800  

 Later we will use this method to determine future amounts for times longer than one interest period. 

From the perspective of a saver, a lender, or an investor,   interest earned   ( Figure  1–2   b ) is the fi nal amount minus the initial amount, or principal.

Interest  earned total = amount now - principal

 Interest earned over a specifi c period of time is expressed as a percentage of the original amount and is called   rate of return (ROR).




 The time unit for rate of return is called the   interest period,  just as for the borrower’s perspective. Again, the most common period is 1 year.
 
 The term   return on investment (ROI)  is used equivalently with ROR in different industries and settings, especially where large capital funds are committed to engineering-oriented  programs.
 
 The numerical values in Equations [1.2] and [1.4] are the same, but the term   interest rate paid  is more appropriate for the borrower’s perspective, while the   rate of return earned  is better for the investor’s perspective. 

0 comments:

Post a Comment