Stuck on Formula

[parteegolfer]

I have this code that detects the end of a workweek by date in colum
(A)and when the Macro is run it inserts a row with "Weekly Subtotal" i
column (A). There are two issues I can't figuire out:

1) I need to sum up columns above each row till the next "Weekl
Subtotal" is detected. - Coulmns D, E, and F

2) The way the code is now, if I run the Macro for a second time,
duplicate row will be inserted below the last one that was inserted
How can I keep this from happining.

Here is the code:

Sub weekdaycount()
Dim wrng As Range, lrng As Range
Dim count As Long

Set wrng = Cells(8, "a") '<<=== start range - change if need
Set lrng = Cells(Cells.Rows.count, "a").End(xlUp)
Do While (wrng.Row <= lrng.Row)
count = 1
Do While (Weekday(wrng) <= Weekday(wrng(2)))
If wrng(2) <> "" Then
Set wrng = wrng(2)
count = count + 1
Else
Exit Do
End If
Loop
Set wrng = wrng(2)
wrng.EntireRow.Insert
wrng(0) = "Weekly Subtotal"
Loop
End Su