-18.61% is the change from 661 to 538
Calculation steps:
[( 538 - 661 ) ÷ 661] x 100 = -18.61%
Formula
Percentage change = [(538 - 661) / 661] x 100
Subtract the new number by the original number
538 - 661 = -123
-123 ÷ 661 = -0.18608169440242056
-0.18608169440242056 x 100 = -18.61%