-3.38% is the change from 828 to 800
Calculation steps:
[( 800 - 828 ) ÷ 828] x 100 = -3.38%
Formula
Percentage change = [(800 - 828) / 828] x 100
Subtract the new number by the original number
800 - 828 = -28
-28 ÷ 828 = -0.033816425120772944
-0.033816425120772944 x 100 = -3.38%