Excel VBA RoundDown and RoundUp functions

Function TestMin(DMin As Double)

        If DMin < 100 Then

            DMin = WorksheetFunction.RoundDown(DMin, 0)

        ElseIf DMin < 1000 Then

            DMin = WorksheetFunction.RoundDown(DMin, -1)

        ElseIf DMin < 10000 Then

            DMin = WorksheetFunction.RoundDown(DMin, -2)

        ElseIf DMin < 100000 Then

            DMin = WorksheetFunction.RoundDown(DMin, -3)

        ElseIf DMin < 1000000 Then

            DMin = WorksheetFunction.RoundDown(DMin, -4)

        End If

        TestMin = DMin

End Function

Function TestMax(DMax As Double)

        If DMax < 100 Then

            DMax = WorksheetFunction.RoundUp(DMax, 0)

        ElseIf DMax < 1000 Then

            DMax = WorksheetFunction.RoundUp(DMax, -1)

        ElseIf DMax < 10000 Then

            DMax = WorksheetFunction.RoundUp(DMax, -2)

        ElseIf DMax < 100000 Then

            DMax = WorksheetFunction.RoundUp(DMax, -3)

        ElseIf DMax < 1000000 Then

            DMax = WorksheetFunction.RoundUp(DMax, -4)

        End If

        TestMax = DMax

End Function

Sub test()

    MsgBox TestMin(87789.89)

    MsgBox TestMax(97979.89)

End Sub