32.66% is the change from 640 to 849
Calculation steps:
[( 849 - 640 ) ÷ 640] x 100 = 32.66%
Formula
Percentage change = [(849 - 640) / 640] x 100
Subtract the new number by the original number
849 - 640 = 209
209 ÷ 640 = 0.3265625
0.3265625 x 100 = 32.66%