Question : MS Access calculate rolling 12 month average

In an Access query how do I calculate a rolling 12 month average for a field that contains numerical data such as 1, 2, 3.  The fields are Date (month/year), number of injuries, and the 3rd column will contain a rolling 12 month average for the past 12 months.

Answer : MS Access calculate rolling 12 month average

Use a criterium like:

  where [YourDateField] between DateAdd("yyyy", -1, Date()) and Date()

If [YourDateField] is not of data type Date you will have to convert it to a valid date value using DateValue or DateSerial.

/gustav