If you can do without a count of the occurances and simply wish to check if the value x exists in the column of y's, then returning a boolean TRUE or FALSE with the ISNUMBER function evaluating a MATCH function lookup will greatly speed up the process.
=ISNUMBER(MATCH(S1, Y:Y, 0))
Fill down as necessary to catch all returns. Sort and/or filter the returned values to tabulate results.
Addendum:
Apparently there is. The huge improvement in the MATCH function calculation times over the COUNTIF function made me wonder if MATCH couldn't be put into a loop, advancing the first cell in its lookup_array parameter to the previously returned row number plus one until there were no more matches. Additionally, subsequent MATCh calls to lookup the same number (increasing the count) could be made to increasingly smaller lookup_array cell ranges by resizing (shrinking) the height of the column by the returned row number as well. If the processed values and their counts were stored as keys and items in a scripting dictionary, duplicate values could be instantly resolved without processing a count.
Sub formula_countif_test()
Dim tmr As Double
appOFF
tmr = Timer
With Sheet2.Cells(1, 1).CurrentRegion
With .Offset(1, 0).Resize(.Rows.Count - 1, .Columns.Count) 'skip header
.Cells(1, 3).Resize(.Rows.Count, 1).FormulaR1C1 = _
"=countif(c1, rc2)" 'no need for calculate when blocking in formulas like this
End With
End With
Debug.Print "COUNTIF formula: " & Timer - tmr
appON
End Sub
Sub formula_match_test()
Dim rw As Long, mrw As Long, tmr As Double, vKEY As Variant
'the following requires Tools, References, Microsoft Scripting Dictionary
Dim dVALs As New Scripting.dictionary
dVALs.CompareMode = vbBinaryCompare 'vbtextcompare for non-case sensitive
appOFF
tmr = Timer
With Sheet2.Cells(1, 1).CurrentRegion
With .Offset(1, 0).Resize(.Rows.Count - 1, .Columns.Count) 'skip header
For rw = 1 To .Rows.Count
vKEY = .Cells(rw, 2).Value2
If Not dVALs.Exists(vKEY) Then
dVALs.Add Key:=vKEY, _
Item:=Abs(IsNumeric(Application.Match(vKEY, .Columns(1), 0)))
If CBool(dVALs.Item(vKEY)) Then
mrw = 0: dVALs.Item(vKEY) = 0
Do While IsNumeric(Application.Match(vKEY, .Columns(1).Offset(mrw, 0).Resize(.Rows.Count - mrw + 1, 1), 0))
mrw = mrw + Application.Match(vKEY, .Columns(1).Offset(mrw, 0).Resize(.Rows.Count - mrw + 1, 1), 0)
dVALs.Item(vKEY) = CLng(dVALs.Item(vKEY)) + 1
Loop
End If
.Cells(rw, 3) = CLng(dVALs.Item(vKEY))
Else
.Cells(rw, 3) = CLng(dVALs.Item(vKEY))
End If
Next rw
End With
End With
Debug.Print "MATCH formula: " & Timer - tmr
dVALs.RemoveAll: Set dVALs = Nothing
appON
End Sub
Sub appON(Optional ws As Worksheet)
Application.ScreenUpdating = True
Application.EnableEvents = True
Application.Calculation = xlCalculationAutomatic
End Sub
Sub appOFF(Optional ws As Worksheet)
Application.ScreenUpdating = False
Application.EnableEvents = False
Application.Calculation = xlCalculationManual
End Sub
????????
I used 10K rows with columns A and B filled by RANDBETWEEN(1, 999)
then copied and pasted as values.
Elapsed times:
?
????Test 11 - 10K rows × 2 columns filled with RANDBETWEEN(1, 999)
????????COUNTIF formula:???????????15.488 seconds
????????MATCH formula:????????????????1.592 seconds?
?
????Test 22 - 10K rows × 2 columns filled with RANDBETWEEN(1, 99999)
????????COUNTIF formula:???????????14.722 seconds
????????MATCH formula:????????????????3.484 seconds?
?
I also copied the values from the COUNTIF formula into another column and compared them to the ones returned by the coded MATCH function. They were identical across the 10K rows.?
???1 More multiples; less zero counts?
???2 More zero counts, less multiples?
While the nature of the data clearly makes a significant difference, the coded MATCH function outperformed the native COUNTIF worksheet function every time.
Don't forget the VBE's Tools ? References ? Microsoft Scripting Dictionary.