-66.25% is the change from 637 to 215
Calculation steps:
[( 215 - 637 ) ÷ 637] x 100 = -66.25%
Formula
Percentage change = [(215 - 637) / 637] x 100
Subtract the new number by the original number
215 - 637 = -422
-422 ÷ 637 = -0.6624803767660911
-0.6624803767660911 x 100 = -66.25%