-79.68% is the change from 251 to 51
Calculation steps:
[( 51 - 251 ) ÷ 251] x 100 = -79.68%
Formula
Percentage change = [(51 - 251) / 251] x 100
Subtract the new number by the original number
51 - 251 = -200
-200 ÷ 251 = -0.796812749003984
-0.796812749003984 x 100 = -79.68%