42400% is the change from 2 to 850
Calculation steps:
[( 850 - 2 ) ÷ 2] x 100 = 42400%
Formula
Percentage change = [(850 - 2) / 2] x 100
Subtract the new number by the original number
850 - 2 = 848
848 ÷ 2 = 424
424 x 100 = 42400%
Example