55.94% is the change from 640 to 998
Calculation steps:
[( 998 - 640 ) ÷ 640] x 100 = 55.94%
Formula
Percentage change = [(998 - 640) / 640] x 100
Subtract the new number by the original number
998 - 640 = 358
358 ÷ 640 = 0.559375
0.559375 x 100 = 55.94%