-61.15% is the change from 646 to 251
Calculation steps:
[( 251 - 646 ) ÷ 646] x 100 = -61.15%
Formula
Percentage change = [(251 - 646) / 646] x 100
Subtract the new number by the original number
251 - 646 = -395
-395 ÷ 646 = -0.6114551083591331
-0.6114551083591331 x 100 = -61.15%