-49.64% is the change from 834 to 420
Calculation steps:
[( 420 - 834 ) ÷ 834] x 100 = -49.64%
Formula
Percentage change = [(420 - 834) / 834] x 100
Subtract the new number by the original number
420 - 834 = -414
-414 ÷ 834 = -0.49640287769784175
-0.49640287769784175 x 100 = -49.64%