-89.9% is the change from 485 to 49
Calculation steps:
[( 49 - 485 ) ÷ 485] x 100 = -89.9%
Formula
Percentage change = [(49 - 485) / 485] x 100
Subtract the new number by the original number
49 - 485 = -436
-436 ÷ 485 = -0.8989690721649485
-0.8989690721649485 x 100 = -89.9%