-83.6% is the change from 311 to 51
Calculation steps:
[( 51 - 311 ) ÷ 311] x 100 = -83.6%
Formula
Percentage change = [(51 - 311) / 311] x 100
Subtract the new number by the original number
51 - 311 = -260
-260 ÷ 311 = -0.8360128617363344
-0.8360128617363344 x 100 = -83.6%