-40% is the change from 10 to 6
Calculation steps:
[( 6 - 10 ) ÷ 10] x 100 = -40%
Formula
Percentage change = [(6 - 10) / 10] x 100
Subtract the new number by the original number
6 - 10 = -4
-4 ÷ 10 = -0.4
-0.4 x 100 = -40%
Example