-83.78% is the change from 407 to 66
Calculation steps:
[( 66 - 407 ) ÷ 407] x 100 = -83.78%
Formula
Percentage change = [(66 - 407) / 407] x 100
Subtract the new number by the original number
66 - 407 = -341
-341 ÷ 407 = -0.8378378378378378
-0.8378378378378378 x 100 = -83.78%