Dim PurchaseDate = Loan.Fields("3567").Value
Dim endDate = Month(DateAdd("m", -1, PurchaseDate)) & "/" & "01" & "/" & Year(DateAdd("m", -1, PurchaseDate))
Dim beginDate = PurchaseDate
Dim beginDay = Day(beginDate)
Dim endDay = Day(endDate)

If Month(beginDate) = 2 And (beginDay = 28 Or beginDay = 29) And Month(endDate) = 2 And (endDay = 28 Or endDay = 29) Then
    endDay = 30
Else If beginDay = 31 And Month(endDate) = 2 And (endDay = 28 Or endDay = 29) Then
    beginDay = 30
Else If beginDay = 30 And endDay = 31 Then
    endDay = 30
End If

Dim days = (Year(endDate) - Year(beginDate)) * 360 + (Month(endDate) - Month(beginDate)) * 30 + (endDay - beginDay) * -1