VBA code to run once within Worksheet_SelectionChange

[Elysium4Eternity]

Hello, there is a code where I'm being struggling with. I have this:

   Range("A70").Value = Date 
    If Range("A70").Value = "01/01/2019" Then
    Range("A71").Value = Range("A71").Value * 1.02
    End If

Withen an rivate Sub Worksheet_SelectionChange(ByVal Target As Range)

But I only need it to run once when I open the file on 01/01/2019 and not every time I click on my worksheet.

 

[footoo]

If Date = DateValue("1/1/2019") And Range("A70")<>Date Then
    Range("A70") = Date
    Range("A71") = Range("A71") * 1.02
End If

Suggest put it a Workbook_Open procedure - would need to specify the relevant sheet in the code.