-51.96% is the change from 637 to 306
Calculation steps:
[( 306 - 637 ) ÷ 637] x 100 = -51.96%
Formula
Percentage change = [(306 - 637) / 637] x 100
Subtract the new number by the original number
306 - 637 = -331
-331 ÷ 637 = -0.5196232339089482
-0.5196232339089482 x 100 = -51.96%