2.64% is the change from 644 to 661
Calculation steps:
[( 661 - 644 ) ÷ 644] x 100 = 2.64%
Formula
Percentage change = [(661 - 644) / 644] x 100
Subtract the new number by the original number
661 - 644 = 17
17 ÷ 644 = 0.026397515527950312
0.026397515527950312 x 100 = 2.64%