-50.54% is the change from 839 to 415
Calculation steps:
[( 415 - 839 ) ÷ 839] x 100 = -50.54%
Formula
Percentage change = [(415 - 839) / 839] x 100
Subtract the new number by the original number
415 - 839 = -424
-424 ÷ 839 = -0.5053635280095352
-0.5053635280095352 x 100 = -50.54%