-40% is the change from 835 to 501
Calculation steps:
[( 501 - 835 ) ÷ 835] x 100 = -40%
Formula
Percentage change = [(501 - 835) / 835] x 100
Subtract the new number by the original number
501 - 835 = -334
-334 ÷ 835 = -0.4
-0.4 x 100 = -40%
Example