-94.23% is the change from 520 to 30
Calculation steps:
[( 30 - 520 ) ÷ 520] x 100 = -94.23%
Formula
Percentage change = [(30 - 520) / 520] x 100
Subtract the new number by the original number
30 - 520 = -490
-490 ÷ 520 = -0.9423076923076923
-0.9423076923076923 x 100 = -94.23%