-77.31% is the change from 661 to 150
Calculation steps:
[( 150 - 661 ) ÷ 661] x 100 = -77.31%
Formula
Percentage change = [(150 - 661) / 661] x 100
Subtract the new number by the original number
150 - 661 = -511
-511 ÷ 661 = -0.773071104387292
-0.773071104387292 x 100 = -77.31%