-65.1% is the change from 490 to 171
Calculation steps:
[( 171 - 490 ) ÷ 490] x 100 = -65.1%
Formula
Percentage change = [(171 - 490) / 490] x 100
Subtract the new number by the original number
171 - 490 = -319
-319 ÷ 490 = -0.6510204081632653
-0.6510204081632653 x 100 = -65.1%