adding to a date to show an end date

Hello,

I'm relatively familiar with Access, but have not used it in a long time. I am now setting up a new database which tracks employee discipline. My company has the following set of rules:

If an employee has more than two occurences of calling in sick or being late in a 30 day period, the employee receives a letter.

After 60 days of having perfect attendance, the letter level is reduced by one.

After 90 days, the letter is no longer active, not matter what.

In this database table, I have one cell that shows when the last letter was issued in 1 of 3 categories. In the next, I want it to show when that letter would no longer be in effect (going by the 90 days later rule). In essence, if a letter would be issued today, that date would be entered into the 5th cell, and in the 6th it would show the date 90 days from today, and highlight it yellow.

Additionally, I would like the 4th cell to count cells 5, 7, 9, and 11. If they have a date in them, it should count each one, giving me a total number of active letters.

So, this is what I'm looking for. I'm sure it's pretty elementary, and at one point, I would like to imagine I knew this. But I haven't touched access in 4 years!

Thanks for any help.