-15.25% is the change from 400 to 339
Calculation steps:
[( 339 - 400 ) ÷ 400] x 100 = -15.25%
Formula
Percentage change = [(339 - 400) / 400] x 100
Subtract the new number by the original number
339 - 400 = -61
-61 ÷ 400 = -0.1525
-0.1525 x 100 = -15.25%