Public Function StrRaul01(ByVal Number As Long) As String
    If Number And &H80000000 Then
        StrRaul01 = "-"
        Number = Number * -1
    End If
    If Number = 0 Then StrRaul01 = "0": Exit Function
    If Number = 1 Then StrRaul01 = "1": Exit Function
 
    Dim i As Byte
    Do While True
        i = Fix(Number Mod 10)
        Select Case i
            Case 1: StrRaul01 = StrRaul01 & "1"
            Case 2: StrRaul01 = StrRaul01 & "2"
            Case 3: StrRaul01 = StrRaul01 & "3"
            Case 4: StrRaul01 = StrRaul01 & "4"
            Case 5: StrRaul01 = StrRaul01 & "5"
            Case 6: StrRaul01 = StrRaul01 & "6"
            Case 7: StrRaul01 = StrRaul01 & "7"
            Case 8: StrRaul01 = StrRaul01 & "8"
            Case 9: StrRaul01 = StrRaul01 & "9"
            Case 0: StrRaul01 = StrRaul01 & "0"
        End Select
        Select Case Number
            Case Is > 10: Number = Number \ 10
            Case Is = 10
                StrRaul01 = StrRaul01 & "10"
                GoTo Final
            Case Is < 10
                GoTo Final
        End Select
    Loop
Final:
    StrRaul01 = StrReverse(StrRaul01)
    Dim s As String
    Dim t As Integer
    Dim l As Integer
    t = 1
    l = Len(StrRaul01)
    If l = 1 Then Exit Function
    For i = 1 To l
        If Mid$(StrRaul01, i, 1) = "0" Then
            t = t + 1
        Else
            StrRaul01 = Mid(StrRaul01, t)
            Exit Function
        End If
    Next
End Function
 

Private Declare Function GetTickCount Lib "kernel32" () As Long

Option Explicit
Private Declare Function GetTickCount Lib "kernel32" () As Long
 
Private Sub Form_Load()
    Dim t1 As Long
    Dim t2 As Long
 
    t1 = GetTickCount '1ª marca
 
    'Call Function
 
    t2 = GetTickCount '2ª marca
 
    MsgBox t2 - t1    'Resultado = diferencia entre marcas.
 
End Sub

Option Explicit
 
Dim tmr As CTiming
 
Private Sub Form_Load()
    Set tmr = New CTiming
 
    tmr.Reset
 
    Debug.Print StrRaul01(-99999)
 
    MsgBox tmr.Elapsed
 
End Sub