-51.45% is the change from 517 to 251
Calculation steps:
[( 251 - 517 ) ÷ 517] x 100 = -51.45%
Formula
Percentage change = [(251 - 517) / 517] x 100
Subtract the new number by the original number
251 - 517 = -266
-266 ÷ 517 = -0.5145067698259188
-0.5145067698259188 x 100 = -51.45%