Percent change explained
For a second, imagine yourself as a kid again. You get an allowance each week and store it in your piggy bank.
Being the intelligent child that you are, you want to track how your weekly allowance is fluctuating. However, instead of just seeing the +/- in dollars, you want to see what percent your allowance is growing/shrinking.
The percent change formula enables us to monitor the changing of values over time.
Coding Percent change
Given the above situation, let's figure out how they calculated the percent change for each of the weekly allowances.
First, here is the formula for percent change: