-45.18% is the change from 830 to 455
Calculation steps:
[( 455 - 830 ) ÷ 830] x 100 = -45.18%
Formula
Percentage change = [(455 - 830) / 830] x 100
Subtract the new number by the original number
455 - 830 = -375
-375 ÷ 830 = -0.45180722891566266
-0.45180722891566266 x 100 = -45.18%