[SteveG1972]

I have more questions about excel formula. In one column I have data appearing, as either a 1 or 2, at random as I input it. Each column has around 120 rows. In the row at the bottom I created a formula to calculate how often, on average, the data appears in that column. 1st how do I get each row to represent a date. 2nd how can I get the sheet to show the next expected date that the data may appear in that column, taking into account the date it last appeared and the average between appearances?

[JBeaucaire]

1st how do I get each row to represent a date.

1. You add an actual new column and put dates into it to go with the data you're putting in the other two field.

2nd how can I get the sheet to show the next expected date that the data may appear in that column, taking into account the date it last appeared and the average between appearances?

That's harder.

First you have to count all the dates, since that will be the only column with something in every cell.
=COUNTA(A2:A100)
Adjust that range to match your data.

Then count the number of entries in a column
=COUNTA(B2:B100)
Also make sure you've adjusted you formula to reflect the same number of rows as the first formula above.

Now divide the two numbers above and add that to the date of the last entry. Make sure that last cell is formatted to display as a DATE.

A workbook examples is attached.