-86.25% is the change from 509 to 70
Calculation steps:
[( 70 - 509 ) ÷ 509] x 100 = -86.25%
Formula
Percentage change = [(70 - 509) / 509] x 100
Subtract the new number by the original number
70 - 509 = -439
-439 ÷ 509 = -0.862475442043222
-0.862475442043222 x 100 = -86.25%