excel vba step thru rows faster

Question

the code below works 100%. It scans for a match in Column B and copies and renames a group of cells when a match is found. However the is a line For lRow = Sheets("HR-Calc").Cells(Cells.Rows.count, "b").End(xlUp).Row To 7 Step -1 Where the step -1 will scan row by row from the bottom of the sheet until a match is found. It would be much easier if the step was set to End.(xlUp) instead of -1 . searching every row is overkill because of how the data is set up End.(xlUp) would massive cut down the run time. Is something like this possible?

Sub Fill_CB_Calc()

M_Start:

Application.ScreenUpdating = True

Sheets("summary").Activate
d_input = Application.InputBox("select first cell in data column", "Column Data Check", Default:="", Type:=8).Address(ReferenceStyle:=xlA1, RowAbsolute:=True, ColumnAbsolute:=False)

data_col = Left(d_input, InStr(2, d_input, "$") - 1)
data_row = Right(d_input, Len(d_input) - InStr(2, d_input, "$"))

Application.ScreenUpdating = False

Sheets("summary").Activate
Range(d_input).End(xlDown).Select

data_last = ActiveCell.Row

If IsEmpty(Range(data_col & data_row + 1)) = True Then
    data_last = data_row

Else
End If

    For j = data_row To data_last

CBtype = Sheets("summary").Range(data_col & j)

    Sheets("HR-Calc").Activate
    For lRow = Sheets("HR-Calc").Cells(Cells.Rows.count, "b").End(xlUp).Row To 7 Step -1

    If Sheets("HR-Calc").Cells(lRow, "b") = CBtype Then

            CBend = Sheets("HR-Calc").Range("C" & lRow).End(xlDown).Row + 1
            Sheets("HR-Calc").Rows(lRow & ":" & CBend).Copy

            CBstart = Sheets("HR-Calc").Range("c50000").End(xlUp).Row + 2

            ActiveWindow.ScrollRow = CBstart - 8

            Sheets("HR-Calc").Range("A" & CBstart).Insert Shift:=xlDown

            CBold = Right(Range("c" & CBstart), Len(Range("C" & CBstart)) - 2)

                box_name = Sheets("summary").Range(data_col & j).Offset(0, -10)

                CBnew = Right(box_name, Len(box_name) - 2) & "-"  ' <--this is custom and can be changed based on CB naming structure
                If CBnew = "" Or vbCancel Then
                End If
            CBend2 = Range("c50000").End(xlUp).Row - 2

            Range("C" & CBstart + 1 & ":" & "C" & CBend2).Select
                Selection.Replace What:=CBold & "-", Replacement:=CBnew, LookAt:=xlPart, _
                SearchOrder:=xlByRows, MatchCase:=False, SearchFormat:=False, _
                ReplaceFormat:=False

            Range("C" & CBstart).FormulaR1C1 = "CB" & Left(CBnew, Len(CBnew) - 1)

            GoTo M_Start2
    Else

    End If

Next lRow
M_Start2:
            Next j

YN_result = MsgBox("Fill info for another block/inverter?", vbYesNo + vbExclamation)
If YN_result = vbYes Then GoTo M_Start
If YN_result = vbNo Then GoTo jumpout

jumpout:
'    Sheets("summary").Range(d_input).Select
    Application.ScreenUpdating = True
End Sub

Answer 1

I'm not sure if this will help but I've had a great performance increase with pulling the entire range you need to loop through into a variant array and then looping through the array. If I need to loop through large data sets, this method has worked out well.

Dim varArray as Variant
varArray = Range(....) 'set varArray to the range you're looping through
For y = 1 to uBound(varArray,1)  'loops through rows of the array
    'code for each row here
    'to loop through individual columns in that row, throw in another loop
    For x = 1 to uBound(varArray, 2) 'loop through columns of array
       'code here
    Next x
Next y

You can also define the column indexes prior to executing the loop. Then you only need to execute the you need to pull those directly in the loop.

'prior to executing the loop, define the column index of what you need to look at
Dim colRevenue as Integer
colRevenue = 5 'or a find function that searches for a header named "Revenue"

Dim varArray as Variant
    varArray = Range(....) 'set varArray to the range you're looping through
For y = 1 to uBound(varArray,1)  'loops through rows of the array
    tmpRevenue = CDbl(varArray(y, colRevenue))
Next y

Hope this helps.

Answer 2

Look at doing a .find from the bottom up.

Perform a FIND, within vba, from the bottom of a range up

That will eliminate the need to do the for loop from the last row to the first occurrence of the value you want to locate.