Creating calculated field from parameter results in query

[Kat2016]

I am attempting to create a query that will be able to calculate the average amount earned within a set amount of days.



The amount of days this average would be based on depends on what the user will enter into the parameters.

The activity_date is my field where the parameters are set, and the net_sales is the amount I will be averaging from the days chosen.

Is there a way I can create a calculated field that is based on parameter results?

Would really appreciate the help.

Thanks

[ranman256]

Yes, if the parameter in the query is [Enter Days]
then just ad this param into the calc:

example:
MyCalc: sum([Enter Days])*301/[Enter Days]

[Kat2016]

The parameter is: between [Start Date] and [End Date]

I'm very new to this. Why would I be multiplying by 301?

[Kat2016]

Since I am using between would it be entered into the calculation differently?

[ranman256]

301 that was an example.

I would use a form, Let the user enter start date ,end date in the boxes. txtStartDate, txtEndDate.
A 3rd box txtDays would calc days. txtDays.rowsource = DateDiff("d",txtStartDate,txtEndDate)

now the query only has 1 param in the calc.
select *,Count([id])/forms!frmRpt!txtDays AS AVG from table where [date] between forms!frmRpt!txtStartDate and forms!frmRpt!txtEndDate

[Kat2016]

Thank you for your help.