-51.73% is the change from 839 to 405
Calculation steps:
[( 405 - 839 ) ÷ 839] x 100 = -51.73%
Formula
Percentage change = [(405 - 839) / 839] x 100
Subtract the new number by the original number
405 - 839 = -434
-434 ÷ 839 = -0.5172824791418356
-0.5172824791418356 x 100 = -51.73%