-32% is the change from 450 to 306
Calculation steps:
[( 306 - 450 ) ÷ 450] x 100 = -32%
Formula
Percentage change = [(306 - 450) / 450] x 100
Subtract the new number by the original number
306 - 450 = -144
-144 ÷ 450 = -0.32
-0.32 x 100 = -32%
Example