Autofill Application.Countifs.Formula VBA Excel - vba

Question

I think this might be a simple question but I can't seem to find a way to autofill an Application.WorksheetFunction.SumProduct(wsf.CountIf formula so that the row number would change as the formula goes down.
I want to autofill this formula for B2 till LastRow from Column A
Application.WorksheetFunction.SumProduct(wsf.CountIfs(Sheet2.Range(**B2 Here**), Doctors, Sheet2.Range(**B2 Here**), wsf.Transpose(Emergency)))
So lets assume that the last used row for column A is 6, so the formula should autofill from B2 until B6 such as:
B3 = Application.WorksheetFunction.SumProduct(wsf.CountIfs(Sheet2.Range(**B3 Here**)....
B4 = Application.WorksheetFunction.SumProduct(wsf.CountIfs(Sheet2.Range(**B4 Here**)....
B5 = Application.WorksheetFunction.SumProduct(wsf.CountIfs(Sheet2.Range(**B5 Here**)....
B6 = Application.WorksheetFunction.SumProduct(wsf.CountIfs(Sheet2.Range(**B6 Here**)....
I don't want to use .Formula "=SUMPRODUCT(COUNTIFS....." approach so that I can use arrays as the criteria vary according to the selected dropdown choices.
Any clues?

Answer 1

AutoFill can do this for you. Assuming your formula begins in B2 and the end row changes, the syntax would be:
LRow = Sheet1.Cells(Rows.Count,1).End(xlUp).Row
With Range("B2")
.Formula = 'Your formula here.
.AutoFill Destination:=Range("B2:B" & LRow)
End With
Another option would be using FillDown as AutoFill almost always have quirks. The syntax is pretty much the same:
LRow = Sheet1.Cells(Rows.Count,1).End(xlUp).Row
Sheet1.Range("B2").Formula = 'Your formula here.
Sheet1.Range("B2:B" & LRow).FillDown
Let us know if this helps.
UPDATE:
Much like Dave's answer, here's my take on your formula:
Sub Test()
Dim Sh As Worksheet
Set Sh = ThisWorkbook.Sheets("Sheet1") 'Modify as required.
With Sh
LRow = .Cells(Rows.Count, 1).End(xlUp.Row)
.Range("B2").Formula = "=SUMPRODUCT(COUNTIFS($C$2:$C$16, ""Doctors"", $I$2:$I$16, $B2))"
.Range("B2:B" & LRow).FillDown
End With
End Sub
HOWEVER, here's the clincher: If you are merely doing a COUNTIFS checking if Column C has Doctors as value and Column I has the value of B2, you should remove the SUMPRODUCT from your formula as it's not necessary. SUMPRODUCT was once the way to check multiple conditions, but in Excel 2007 and up, it's been completely replaced by COUNTIFS for simple multiple condition-based check-and-count. What I'm saying is, the proper code is pretty much the following:
Sub Test()
Dim Sh As Worksheet
Set Sh = ThisWorkbook.Sheets("Sheet1") 'Modify as required.
With Sh
LRow = .Cells(Rows.Count, 1).End(xlUp.Row)
.Range("B2").Formula = "=COUNTIFS($C$2:$C$16, ""Doctors"", $I$2:$I$16, $B2)"
.Range("B2:B" & LRow).FillDown
End With
End Sub
STILL, further formula forensics and evaluation reveal a trickier part: You are entering your formula in B2 and below, but your COUNTIFS is checking B2 and below as part of the condition as well. This is not only confusing but is also prone to error (if not already erroneous) as it will result into a circular reference.
At this point, my question now is, what exactly are you trying to check and/or count? This is more than just a VBA issue, in my opinion, as I believe that you are confused as to what and how you want to get your numbers. While our approach is sound and is basically perfect for your question, if the formula is incorrect, the above is useless. :)

Answer 2

Try this.
Here's how my data is laid out:
This code goes in regular module:
Sub Test(s As String) 'input frpm combo box
Dim Sh As Worksheet, LRow As Long
Set Sh = ThisWorkbook.Sheets("Sheet1") 'Modify as required.
If LCase(s) = "all" Then s = "*"
s = Chr(34) & s & Chr(34) 'bracket with quotes
With Sh
LRow = .Cells(Rows.Count, 1).End(xlUp).Row
.Range("B2").Formula = "=COUNTIFS($C$2:$C$16," & s & ", $I$2:$I$16, $A2)"
.Range("B2:B" & LRow).FillDown
End With
End Sub
This code goes in sheet module of combo box (Sheet1 in this instance).
Private Sub ComboBox1_Change()
Test Me.ComboBox1.Value
End Sub
I'm not sure of your formula results, but it is getting loaded correctly.