-21.79% is the change from 661 to 517
Calculation steps:
[( 517 - 661 ) ÷ 661] x 100 = -21.79%
Formula
Percentage change = [(517 - 661) / 661] x 100
Subtract the new number by the original number
517 - 661 = -144
-144 ÷ 661 = -0.2178517397881997
-0.2178517397881997 x 100 = -21.79%