-93.89% is the change from 491 to 30
Calculation steps:
[( 30 - 491 ) ÷ 491] x 100 = -93.89%
Formula
Percentage change = [(30 - 491) / 491] x 100
Subtract the new number by the original number
30 - 491 = -461
-461 ÷ 491 = -0.9389002036659878
-0.9389002036659878 x 100 = -93.89%