27900% is the change from 1 to 280
Calculation steps:
[( 280 - 1 ) ÷ 1] x 100 = 27900%
Formula
Percentage change = [(280 - 1) / 1] x 100
Subtract the new number by the original number
280 - 1 = 279
279 ÷ 1 = 279
279 x 100 = 27900%
Example