-90.91% is the change from 561 to 51
Calculation steps:
[( 51 - 561 ) ÷ 561] x 100 = -90.91%
Formula
Percentage change = [(51 - 561) / 561] x 100
Subtract the new number by the original number
51 - 561 = -510
-510 ÷ 561 = -0.9090909090909091
-0.9090909090909091 x 100 = -90.91%