Follow the instructions below using the superstore data. For the most recent Month calcuation I keep getting the error you cannot mix aggreate and non-aggreate arugments using this function. Is there anyway to fix this?

Calculate the last day of the last fully completed month. Call the calculation [Last Day of Last Full Month]:

// Last Day of Last Full Month

DATETRUNC("month", [Max Date] + 1) - 1

Calculate the start of the last fully complete month. Call the calculation [First Day of Last Full Month]:

// First Day of Last Full Month

DATETRUNC("month", [Last Day of Last Full Month])

Now create another calculation called [Most Recent Month]:

// Most Recent Month

[Order Date] >= [First Day of Last Full Month]

AND

[Order Date] <= [Last Day of Last Full Month]