-20.03% is the change from 634 to 507
Calculation steps:
[( 507 - 634 ) ÷ 634] x 100 = -20.03%
Formula
Percentage change = [(507 - 634) / 634] x 100
Subtract the new number by the original number
507 - 634 = -127
-127 ÷ 634 = -0.20031545741324921
-0.20031545741324921 x 100 = -20.03%