2027.5% is the change from 40 to 851
Calculation steps:
[( 851 - 40 ) ÷ 40] x 100 = 2027.5%
Formula
Percentage change = [(851 - 40) / 40] x 100
Subtract the new number by the original number
851 - 40 = 811
811 ÷ 40 = 20.275
20.275 x 100 = 2027.5%
Example