-87.22% is the change from 399 to 51
Calculation steps:
[( 51 - 399 ) ÷ 399] x 100 = -87.22%
Formula
Percentage change = [(51 - 399) / 399] x 100
Subtract the new number by the original number
51 - 399 = -348
-348 ÷ 399 = -0.8721804511278195
-0.8721804511278195 x 100 = -87.22%