19.72% is the change from 284 to 340
Calculation steps:
[( 340 - 284 ) ÷ 284] x 100 = 19.72%
Formula
Percentage change = [(340 - 284) / 284] x 100
Subtract the new number by the original number
340 - 284 = 56
56 ÷ 284 = 0.19718309859154928
0.19718309859154928 x 100 = 19.72%