-50.1% is the change from 517 to 258
Calculation steps:
[( 258 - 517 ) ÷ 517] x 100 = -50.1%
Formula
Percentage change = [(258 - 517) / 517] x 100
Subtract the new number by the original number
258 - 517 = -259
-259 ÷ 517 = -0.5009671179883946
-0.5009671179883946 x 100 = -50.1%