-80.95% is the change from 210 to 40
Calculation steps:
[( 40 - 210 ) ÷ 210] x 100 = -80.95%
Formula
Percentage change = [(40 - 210) / 210] x 100
Subtract the new number by the original number
40 - 210 = -170
-170 ÷ 210 = -0.8095238095238095
-0.8095238095238095 x 100 = -80.95%