-74.89% is the change from 661 to 166
Calculation steps:
[( 166 - 661 ) ÷ 661] x 100 = -74.89%
Formula
Percentage change = [(166 - 661) / 661] x 100
Subtract the new number by the original number
166 - 661 = -495
-495 ÷ 661 = -0.7488653555219364
-0.7488653555219364 x 100 = -74.89%