Question

DateDiff calculates incorrect:

DateDiff("m", "30/06/2011", "24/06/2012") will return 12

But i need to return 11,because real difference is 11 months and 25 days

Maybe anyone have specific solution for this question

That will be ideal for me: 11 months and 25 days

Answer 1

Here’s a cleaner solution than the above custom made function. Mostly it uses the built-in DateDiff function, but then adjusts the answer if it rounds up.
My function will also give you the difference even if the the first date is later than the second and optionally add some text saying so.

Function YearsMonthsDays(Date1 As Date, _
                     Date2 As Date, _
                     Optional ShowAll As Boolean = False, _
                     Optional Grammar As Boolean = True, _
                     Optional MinusText As String = "Minus " _
                     ) As String
Dim dTempDate As Date
Dim iYears As Integer
Dim iMonths As Integer
Dim iDays As Integer
Dim sYears As String
Dim sMonths As String
Dim sDays As String
Dim sGrammar(-1 To 0) As String
Dim sMinusText As String

If Grammar = True Then
    sGrammar(0) = "s"
End If


If Date1 > Date2 Then
    dTempDate = Date1
    Date1 = Date2
    Date2 = dTempDate
    sMinusText = MinusText
End If

iYears = DateDiff("yyyy", Date1, Date2)
Date1 = DateAdd("yyyy", iYears, Date1)
If Date1 > Date2 Then
    iYears = iYears - 1
    Date1 = DateAdd("yyyy", -1, Date1)
End If

iMonths = DateDiff("M", Date1, Date2)
Date1 = DateAdd("M", iMonths, Date1)
If Date1 > Date2 Then
    iMonths = iMonths - 1
    Date1 = DateAdd("m", -1, Date1)
End If

iDays = DateDiff("d", Date1, Date2)

If ShowAll Or iYears > 0 Then
    sYears = iYears & " year" & sGrammar((iYears = 1)) & ", "
End If
If ShowAll Or iYears > 0 Or iMonths > 0 Then
    sMonths = iMonths & " month" & sGrammar((iMonths = 1)) & ", "
End If
sDays = iDays & " day" & sGrammar((iDays = 1))

YearsMonthsDays = sMinusText & sYears & sMonths & sDays
End Function