' Функция получает разницу между датами в заданных единицах даты/времени 
' При ReturnString=True возвращает строковое представление интервала 
Public Function DateInterval(d1 As Date, d2 As Date, _ 
        Optional Years As Variant, Optional Months As Variant, Optional Days As Variant, _ 
        Optional Hours As Variant, Optional Minutes As Variant, Optional Seconds As Variant, _ 
        Optional ReturnString As Boolean = False) As String 
    
    Const sr As String = ", " 
    Const y As String = "yyyy", m As String = "m", d As String = "d", _ 
        h As String = "h", n As String = "n", s As String = "s" 
    Dim dm As Date, dd As Date, dh As Date, dn As Date, ds As Date, _ 
        ss As String, i As Integer, sss As String 

    If IsMissing(Years) Then 
        dm = d1 
    Else 
        Years = DateDiff(y, d1, d2) 
        dm = DateAdd(y, Years, d1) 
        If dm > d2 Then 
            Years = Years -  1  
            dm = DateAdd(y, Years, d1) 
        End If 
        If ReturnString Then 
            ss = Right$(Format$(Years, "00"),  2 ) 
            If Right$(ss,  1 ) = "0" Or Left$(ss,  1 ) = "1" Or CInt(Right$(ss,  1 )) >=  5  Then 
                sss = Years & " лет" 
            Else 
                sss = Years & " год" 
                If Right$(ss,  1 ) <> "1" Then sss = sss & "а" 
            End If 
        End If 
    End If 
    If IsMissing(Months) Then 
        dd = dm 
    Else 
        Months = DateDiff(m, dm, d2) 
        dd = DateAdd(m, Months, dm) 
        If dd > d2 Then 
            Months = Months -  1  
            dd = DateAdd(m, Months, dm) 
        End If 
        If ReturnString Then 
            ss = Right$(Format$(Months, "00"),  2 ) 
            If Len(sss) Then sss = sss & sr 
            sss = sss & Months & " месяц" 
            If Right$(ss,  1 ) = "0" Or Left$(ss,  1 ) = "1" Or CInt(Right$(ss,  1 )) >=  5  Then 
                sss = sss & "ев" 
            Else 
                If Right$(ss,  1 ) <> "1" Then sss = sss & "а" 
            End If 
        End If 
    End If 
    If IsMissing(Days) Then 
        dh = dd 
    Else 
        Days = DateDiff(d, dd, d2) 
        dh = DateAdd(d, Days, dd) 
        If dh > d2 Then 
            Days = Days -  1  
            dh = DateAdd(d, Days, dd) 
        End If 
        If ReturnString Then 
            ss = Right$(Format$(Days, "00"),  2 ) 
            If Len(sss) Then sss = sss & sr 
            sss = sss & Days & " д" 
            If Right$(ss,  1 ) = "0" Or Left$(ss,  1 ) = "1" Or CInt(Right$(ss,  1 )) >=  5  Then 
                sss = sss & "ней" 
            Else 
                sss = sss & IIf(Right$(ss,  1 ) = "1", "ень", "ня") 
            End If 
        End If 
    End If 
    If IsMissing(Hours) Then 
        dn = dh 
    Else 
        Hours = DateDiff(h, dh, d2) 
        dn = DateAdd(h, Hours, dh) 
        If dn > d2 Then 
            Hours = Hours -  1  
            dn = DateAdd(h, Hours, dh) 
        End If 
        If ReturnString Then 
            ss = Right$(Format$(Hours, "00"),  2 ) 
            If Len(sss) Then sss = sss & sr 
            sss = sss & Hours & " час" 
            If Right$(ss,  1 ) = "0" Or Left$(ss,  1 ) = "1" Or CInt(Right$(ss,  1 )) >=  5  Then 
                sss = sss & "ов" 
            Else 
                If Right$(ss,  1 ) <> "1" Then sss = sss & "а" 
            End If 
        End If 
    End If 
    If IsMissing(Minutes) Then 
        ds = dn 
    Else 
        Minutes = DateDiff(n, dn, d2) 
        ds = DateAdd(n, Minutes, dn) 
        If ds > d2 Then 
            Minutes = Minutes -  1  
            ds = DateAdd(n, Minutes, dn) 
        End If 
        If ReturnString Then 
            ss = Right$(Format$(Minutes, "00"),  2 ) 
            If Len(sss) Then sss = sss & sr 
            sss = sss & Minutes & " минут" 
            If Not (Right$(ss,  1 ) = "0" Or Left$(ss,  1 ) = "1" Or CInt(Right$(ss,  1 )) >=  5 ) Then 
                sss = sss & IIf(Right$(ss,  1 ) = "1", "а", "ы") 
            End If 
        End If 
    End If 
    If Not IsMissing(Seconds) Then 
        Seconds = DateDiff(s, ds, d2) 
        If ReturnString Then 
            ss = Right$(Format$(Seconds, "00"),  2 ) 
            If Len(sss) Then sss = sss & sr 
            sss = sss & Seconds & " секунд" 
            If Not (Right$(ss,  1 ) = "0" Or Left$(ss,  1 ) = "1" Or CInt(Right$(ss,  1 )) >=  5 ) Then 
                sss = sss & IIf(Right$(ss,  1 ) = "1", "а", "ы") 
            End If 
        End If 
    End If 
    If ReturnString Then DateInterval = sss 
End Function