If you need to find the percentage change in Excel, especially across a range of cells, then this post offers step by step guidance.

Input the call premium as a percentage in cell B6. The call premium is the percent increase over the bond's face value which is paid by the issuing company to exercise their call option.

If you are not careful in collecting and analyzing the numbers you use to calculate ROI, the percentage Excel calculates will provide a false picture of you business's health.