-27.66% is the change from 423 to 306
Calculation steps:
[( 306 - 423 ) ÷ 423] x 100 = -27.66%
Formula
Percentage change = [(306 - 423) / 423] x 100
Subtract the new number by the original number
306 - 423 = -117
-117 ÷ 423 = -0.2765957446808511
-0.2765957446808511 x 100 = -27.66%