vba code to open excel file name in previous weekday date

Dear all,

I have a Question and would really need help to code it.

i need to open previous week day file always. File name would be like eg, summary22032014.xlsx. say i open this file on 23032014.

So everyday i would need to open previous day file. via vba code......i use below code.

HTML Code: 

The problem is if i execute this code on monday, This code searches for file on previous day date , that is on sunday date.
I need vba code to be corrected to search for file name dated should be logically Friday.

if i execute vba code on Tuesday, it should get file name dated on Monday. and it also should meet....if i execute on monday it should logically search file name
date for Friday. Not a weekend date.

How could i accomplish this.........please help

Sub openbyWorkday()
Dim wb2 As Workbook, ws As Worksheet
Dim spath As String, sfilename As String, NamePart As String
Dim LastWorkDay As Long

spath = "c:\desktop\"
sfilename = "Summary"

LastWorkDay = 1
If LCase(Format(Date, "ddd")) = "mon" Then LastWorkDay = 3

NamePart = sfilename & Format(Date - LastWorkDay, "dd.mm.yyyy") & ".xlsx" '"ddmmyyyy"?

Set wb2 = Workbooks.Open(spath & a)

End Sub