-50% is the change from 430 to 215
Calculation steps:
[( 215 - 430 ) ÷ 430] x 100 = -50%
Formula
Percentage change = [(215 - 430) / 430] x 100
Subtract the new number by the original number
215 - 430 = -215
-215 ÷ 430 = -0.5
-0.5 x 100 = -50%
Example