-98.2% is the change from 833 to 15
Calculation steps:
[( 15 - 833 ) ÷ 833] x 100 = -98.2%
Formula
Percentage change = [(15 - 833) / 833] x 100
Subtract the new number by the original number
15 - 833 = -818
-818 ÷ 833 = -0.9819927971188476
-0.9819927971188476 x 100 = -98.2%