-83.58% is the change from 402 to 66
Calculation steps:
[( 66 - 402 ) ÷ 402] x 100 = -83.58%
Formula
Percentage change = [(66 - 402) / 402] x 100
Subtract the new number by the original number
66 - 402 = -336
-336 ÷ 402 = -0.835820895522388
-0.835820895522388 x 100 = -83.58%