50.86% is the change from 639 to 964
Calculation steps:
[( 964 - 639 ) ÷ 639] x 100 = 50.86%
Formula
Percentage change = [(964 - 639) / 639] x 100
Subtract the new number by the original number
964 - 639 = 325
325 ÷ 639 = 0.5086071987480438
0.5086071987480438 x 100 = 50.86%