26.6% is the change from 639 to 809
Calculation steps:
[( 809 - 639 ) ÷ 639] x 100 = 26.6%
Formula
Percentage change = [(809 - 639) / 639] x 100
Subtract the new number by the original number
809 - 639 = 170
170 ÷ 639 = 0.26604068857589985
0.26604068857589985 x 100 = 26.6%