-20.98% is the change from 634 to 501
Calculation steps:
[( 501 - 634 ) ÷ 634] x 100 = -20.98%
Formula
Percentage change = [(501 - 634) / 634] x 100
Subtract the new number by the original number
501 - 634 = -133
-133 ÷ 634 = -0.20977917981072555
-0.20977917981072555 x 100 = -20.98%