-79.76% is the change from 509 to 103
Calculation steps:
[( 103 - 509 ) ÷ 509] x 100 = -79.76%
Formula
Percentage change = [(103 - 509) / 509] x 100
Subtract the new number by the original number
103 - 509 = -406
-406 ÷ 509 = -0.7976424361493124
-0.7976424361493124 x 100 = -79.76%