3400% is the change from 8 to 280
Calculation steps:
[( 280 - 8 ) ÷ 8] x 100 = 3400%
Formula
Percentage change = [(280 - 8) / 8] x 100
Subtract the new number by the original number
280 - 8 = 272
272 ÷ 8 = 34
34 x 100 = 3400%
Example