-89.7% is the change from 495 to 51
Calculation steps:
[( 51 - 495 ) ÷ 495] x 100 = -89.7%
Formula
Percentage change = [(51 - 495) / 495] x 100
Subtract the new number by the original number
51 - 495 = -444
-444 ÷ 495 = -0.896969696969697
-0.896969696969697 x 100 = -89.7%