-30.38% is the change from 915 to 637
Calculation steps:
[( 637 - 915 ) ÷ 915] x 100 = -30.38%
Formula
Percentage change = [(637 - 915) / 915] x 100
Subtract the new number by the original number
637 - 915 = -278
-278 ÷ 915 = -0.3038251366120219
-0.3038251366120219 x 100 = -30.38%