-98% is the change from 50 to 1
Calculation steps:
[( 1 - 50 ) ÷ 50] x 100 = -98%
Formula
Percentage change = [(1 - 50) / 50] x 100
Subtract the new number by the original number
1 - 50 = -49
-49 ÷ 50 = -0.98
-0.98 x 100 = -98%
Example