-85.71% is the change from 490 to 70
Calculation steps:
[( 70 - 490 ) ÷ 490] x 100 = -85.71%
Formula
Percentage change = [(70 - 490) / 490] x 100
Subtract the new number by the original number
70 - 490 = -420
-420 ÷ 490 = -0.8571428571428571
-0.8571428571428571 x 100 = -85.71%