-17.43% is the change from 631 to 521
Calculation steps:
[( 521 - 631 ) ÷ 631] x 100 = -17.43%
Formula
Percentage change = [(521 - 631) / 631] x 100
Subtract the new number by the original number
521 - 631 = -110
-110 ÷ 631 = -0.17432646592709986
-0.17432646592709986 x 100 = -17.43%