99.8% is the change from 497 to 993
Calculation steps:
[( 993 - 497 ) ÷ 497] x 100 = 99.8%
Formula
Percentage change = [(993 - 497) / 497] x 100
Subtract the new number by the original number
993 - 497 = 496
496 ÷ 497 = 0.9979879275653923
0.9979879275653923 x 100 = 99.8%