Fill Each Cell With Formula

Question

I am attempting to write a macro that will
1) store the value of each cell in column A in a variable searchstring
the pieces of code that I Think does this is

lr = Cells(Rows.Count, 2).End(xlUp).Row
  For i = 2 To lr
      searchstring = ws.Cells(i, 1).Value

2) Take the variable searchstring and determine if it exists in column A of the sheet called rsca.
4) If it does update column N with Yes
5) If it does not update column N with No

This is my full syntax, but everytime I step through my code it hits the For line and immediately jumps to the End Function My worksheet has data in it, column A has roughly 40 rows to be precise (but this could fluctuate up or down, so I do not want to hardcode an end cell)

How should this syntax be altered so that it will achieve my desired result above?

Public Function CheckIfCurrent()
    Dim ws As Worksheet, searchstring As String, i As Long
    Set ws = Sheets("ers")

    lr = Cells(Rows.Count, 2).End(xlUp).Row
    For i = 2 To lr
      searchstring = ws.Cells(i, 1).Value
      With .Range("N2:N" & .Cells(.Rows.Count, "A").End(xlUp).Row)
         .Formula = IIf(IsError(Application.Match(searchstring, Sheets("rsca").Columns(1), 0)), "No", "Yes")
         .Value = .Value
      End With
    Next i        
End Function

Answer 1

How about this?

Public Sub CheckIfCurrent()
    Dim searchstring As String
    Dim i As Long

    With ThisWorkbook.Worksheets("ers")
        lr = .Cells(.Rows.Count, 1).End(xlUp).Row
        For i = 2 To lr
            searchstring = .Cells(i, 1).Value
            With .Range("N2:N" & lr)
                .Formula = IIf(IsError(Application.Match(searchstring, Sheets("rsca").Columns(1), 0)), "No", "Yes")
                .Value = .Value
            End With
        Next i 
    End With 
End Sub