-47.42% is the change from 639 to 336
Calculation steps:
[( 336 - 639 ) ÷ 639] x 100 = -47.42%
Formula
Percentage change = [(336 - 639) / 639] x 100
Subtract the new number by the original number
336 - 639 = -303
-303 ÷ 639 = -0.47417840375586856
-0.47417840375586856 x 100 = -47.42%