34.83% is the change from 623 to 840
Calculation steps:
[( 840 - 623 ) ÷ 623] x 100 = 34.83%
Formula
Percentage change = [(840 - 623) / 623] x 100
Subtract the new number by the original number
840 - 623 = 217
217 ÷ 623 = 0.34831460674157305
0.34831460674157305 x 100 = 34.83%