-21.5% is the change from 428 to 336
Calculation steps:
[( 336 - 428 ) ÷ 428] x 100 = -21.5%
Formula
Percentage change = [(336 - 428) / 428] x 100
Subtract the new number by the original number
336 - 428 = -92
-92 ÷ 428 = -0.21495327102803738
-0.21495327102803738 x 100 = -21.5%