-98.2% is the change from 834 to 15
Calculation steps:
[( 15 - 834 ) ÷ 834] x 100 = -98.2%
Formula
Percentage change = [(15 - 834) / 834] x 100
Subtract the new number by the original number
15 - 834 = -819
-819 ÷ 834 = -0.9820143884892086
-0.9820143884892086 x 100 = -98.2%