So I am trying to calculate 3 columns of numbers (for a register) to equal 100% total and for the absentees to affect the overall percent attendance.

For Example:

```
A1=1
B1=1
D1=1

A1+B1+D1=100% - D1=67%

```

D1 is the absentees and needs to be subtracted from the overall 100%, so in this instance each value is 33.33% as there are three values in total. So A1+B1 would make 67%. How do I formulate this? The formula needs to be scalable (this section has three values but I also need it for four values). Any help will be appreciated.
[Click here for image](https://i.stack.imgur.com/UNtXM.png)