Sequential column numbering with reset

I have a column numbered so...
1
0
0
0
1
0
1
0
0
1
1
0
0
0
0

I would like the next column to number consecutively, starting at 1 each time a 1 is encountered, so my columns would be...
1 1
0 2
0 3
0 4
1 1
0 2
1 1
0 2
0 3
1 1
1 1
0 2
0 3
0 4
0 5

and so on.

I'm at a loss to get this done. Any ideas?

TIA

This should work assuming you have column headers in A1 and B1 and your binary list is in column A:

Sub NumberedList()

    Dim i As Integer
    Dim k As Integer
    Dim cl As Range
    Dim preVal As Integer
    
    ActiveSheet.UsedRange
    
        i = 0
        k = 0
        With ActiveWorkbook.Worksheets
            With [a1]
                For Each cl In Range(.Offset(1, 0), .End(xlDown))
                    If cl.Value <> "" Then
                        i = i + 1
                    End If
                Next cl
            Do Until k = i
                k = k + 1
                If Range(.Offset(k, 0), .Offset(k, 0)).Value = 1 Then
                    Range(.Offset(k, 1), .Offset(k, 1)).Value = 1
                Else
                    preVal = Range(.Offset(k - 1, 1), .Offset(k - 1, 1)).Value
                    Range(.Offset(k, 1), .Offset(k, 1)).Value = preVal + 1
                End If
            Loop
            End With
        End With
End Sub

Thank you, learning_vba! I can follow the code (I'm a software developer, but not VB). I appreciate that.

But my problem now: I'm a real macro dummy in Excel. How do I get what you posted into a spreadsheet and execute it? I've never done that before. Either step-by-step, or point me to a good online help topic. I've been trying to find in Excel help to find something like "How to copy/paste a VBA macro into a spreadsheet" - I haven't found what I need.

Thanks again for taking your time to help this macro newbie!

Got it into a vba form, and executed it. Now I'm getting a type mismatch (error 13) on this line:

preVal = Range(.Offset(k - 1, 1), .Offset(k - 1, 1)).Value

I have copy/pasted my column I'm working with into a new spreadsheet, into cell A1 (added a header to the column). Formatted the column as numeric, 0 decimals...

Here are the first few rows...
Rel RelPlus
1
0
0
1
0
0
0
0
1
0
0

Simplicity at its best! I love it...

Your reputation just got a hit.

Thanks, shg!!