-74.24% is the change from 990 to 255
Calculation steps:
[( 255 - 990 ) ÷ 990] x 100 = -74.24%
Formula
Percentage change = [(255 - 990) / 990] x 100
Subtract the new number by the original number
255 - 990 = -735
-735 ÷ 990 = -0.7424242424242424
-0.7424242424242424 x 100 = -74.24%