You might question why you would add up the displayed figures:

- If you want to just show 100%, then just put that in as text without any
calculation

- If you want to verify your underlying data and manipulations, total up the
unrounded numbers.

- There is nothing that says that a total of rounded numbers is supposed to
= 100%, so, so totaling the rounded numbers does not perform any
verification. And, if you do do this, people who have more personality
defects than brains will nitpick your (non-100%) total.