3.3% is the change from 636 to 657
Calculation steps:
[( 657 - 636 ) ÷ 636] x 100 = 3.3%
Formula
Percentage change = [(657 - 636) / 636] x 100
Subtract the new number by the original number
657 - 636 = 21
21 ÷ 636 = 0.0330188679245283
0.0330188679245283 x 100 = 3.3%