98% is the change from 50 to 99
Calculation steps:
[( 99 - 50 ) ÷ 50] x 100 = 98%
Formula
Percentage change = [(99 - 50) / 50] x 100
Subtract the new number by the original number
99 - 50 = 49
49 ÷ 50 = 0.98
0.98 x 100 = 98%
Example