-89.78% is the change from 499 to 51
Calculation steps:
[( 51 - 499 ) ÷ 499] x 100 = -89.78%
Formula
Percentage change = [(51 - 499) / 499] x 100
Subtract the new number by the original number
51 - 499 = -448
-448 ÷ 499 = -0.8977955911823647
-0.8977955911823647 x 100 = -89.78%