-50.8% is the change from 687 to 338
Calculation steps:
[( 338 - 687 ) ÷ 687] x 100 = -50.8%
Formula
Percentage change = [(338 - 687) / 687] x 100
Subtract the new number by the original number
338 - 687 = -349
-349 ÷ 687 = -0.5080058224163028
-0.5080058224163028 x 100 = -50.8%