-79.59% is the change from 490 to 100
Calculation steps:
[( 100 - 490 ) ÷ 490] x 100 = -79.59%
Formula
Percentage change = [(100 - 490) / 490] x 100
Subtract the new number by the original number
100 - 490 = -390
-390 ÷ 490 = -0.7959183673469388
-0.7959183673469388 x 100 = -79.59%