Find a date

@max(xx:xx) will do it but replicating for each group is out of my scope
q-28138022.xlsx

Hey,
Max will only work if column C stays the same. Use below array formula to capture any variations.

{=MAX(IF($C$2:$C$5=C2,$O$2:$O$5,0))}
Change it to C1 if you don't use headers.
(to make it array formula press CTRL+SHIFT+ENTER)
Max-Array.xls

and then to sort it after the max is completed...

Sub Macro1()
'
' Macro1 Macro
'

'
    Cells.Select
    Application.CutCopyMode = False
    ActiveWorkbook.Worksheets("Sheet1").Sort.SortFields.Clear
    ActiveWorkbook.Worksheets("Sheet1").Sort.SortFields.Add Key:=Range("C:C"), _
        SortOn:=xlSortOnValues, Order:=xlAscending, DataOption:=xlSortNormal
    ActiveWorkbook.Worksheets("Sheet1").Sort.SortFields.Add Key:=Range("AB:AB") _
        , SortOn:=xlSortOnValues, Order:=xlAscending, DataOption:=xlSortNormal
    ActiveWorkbook.Worksheets("Sheet1").Sort.SortFields.Add Key:=Range("O:O") _
        , SortOn:=xlSortOnValues, Order:=xlAscending, DataOption:=xlSortNormal
    With ActiveWorkbook.Worksheets("Sheet1").Sort
        .SetRange Range("A:AB")
        .Header = xlGuess
        .MatchCase = False
        .Orientation = xlTopToBottom
        .SortMethod = xlPinYin
        .Apply
    End With
End Sub

Select allOpen in new window

The formula "=MAX" returns every cell with the same date 23/5/2013

The Macro 'Macro1' removes the header in row 1

is this because I am using 2010?

On further investigation the result in the formula box shows the correct answer of 17/5/2013 but the result shown in the spreadsheet is showing as 24/5/2013.

bizzare

Have attached spreadsheet to assist and show what I mean. Hope someone can resolve this for me.
Book3.xlsx

Hey,
In order to make it work the ranges cannot be full columns.
I have added 2 dynamic named ranges "Ref" and "Entry_Date" this will always bring back correct number of rows.

Please see the attached file for details. Let me know if you need any explanation.
Book3.xlsx

Here are some user-defined functions that will return the maximum value in a range subject to a criteria. Install them in a regular module sheet, then use them with a worksheet formula like:
=MaxIf(A:A,A2,B:B)             'This is a regular formula

Function MaxIf(rgToCheck As Range, Criteria As Variant, rgToMax As Range) As Variant
'Function tests rgToCheck for Criteria. Returns maximum of corresponding cells in rgToMax when rgToCheck cell satisfies Criteria.
'rgToCheck is range to be tested against Criteria
'Criteria may be a single value or an array of values
'rgToMax is range from which the maximum value is selected
'Function returns the maximum value if Criteria is a single value. It returns an array of maximums if Criteria is an array. _
    =MaxIf(A1:A7, ">0",B1:B7)            returns a single value _
    =MaxIf(A1:A7, {">5", "<2"},B1:B7)    returns a two column array of values _
    =MaxIf(A1:A7, {">5"; "<2"},B1:B7)    returns a two row array of values (semicolon instead of comma in array constant) _
    =MaxIf(A1:A7, {">5", ">20"; "<2", "<1"}},B1:B7)   returns a two column by two row array of values
MaxIf = MinMaxIf(rgToCheck, Criteria, rgToMax, False)
End Function

Private Function MinMaxIf(rgToCheck As Range, Criteria As Variant, rgToMinMax As Range, bMinimum As Boolean) As Variant
'Function tests rgToCheck for Criteria. Returns minimum/maximum of corresponding cells in rgToMinMax when rgToCheck cell satisfies Criteria.
'rgToCheck is range to be tested against Criteria
'Criteria may be a single value or an array of values
'rgToMinMax is range from which the minimum/maximum value is selected
'bMinimum is True when function returns a minimum value. It is False if a maximum value is returned.
'Function returns the minimum/maximum value if Criteria is a single value. It returns an array of minimums/maximums if Criteria is an array.

Dim i As Long, ii As Long, j As Long, jj As Long, n As Long, nCols As Long, nRows As Long, nnCols As Long, nnRows As Long
Dim d As Double
Dim iFirstCheck As Integer, iLastCheck As Integer, k As Integer
Dim vCheck As Variant, vCriteria As Variant, vResults As Variant
Dim wbCheck As Workbook

Set rgToCheck = Intersect(rgToCheck, rgToCheck.Worksheet.UsedRange)     'Avoid excessive runtime if needlessly passed entire row or column

nnCols = rgToCheck.Columns.Count
nnRows = rgToCheck.Rows.Count
If nnCols > rgToMinMax.Columns.Count Then
    MinMaxIf = "#ColumnMatch"
    Exit Function
ElseIf nnRows > rgToMinMax.Rows.Count Then
    MinMaxIf = "#RowMatch"
    Exit Function
End If

    'Determine whether Criteria is an array. If so, establish its dimensions.
On Error Resume Next
If VarType(Criteria) >= vbArray Then
    nCols = UBound(Criteria)
    nRows = UBound(Criteria, 2)
    If nCols = 0 Then nCols = 1
    If nRows = 0 Then nRows = 1
    ReDim vResults(1 To nRows, 1 To nCols)
Else
    'ReDim vResults(1 To 1, 1 To 1)
    n = 1
    nRows = 1
    nCols = 1
End If
n = nRows * nCols
On Error GoTo 0

For i = 1 To nRows
    For j = 1 To nCols
        d = IIf(bMinimum, 1E+308, -1E+308)      'Starting value
        If n = 1 Then
            vCriteria = Criteria
        Else
            If nCols = 1 Then
                vCriteria = Criteria(i)
            ElseIf nRows = 1 Then
                vCriteria = Criteria(j)
            Else
                vCriteria = Criteria(i, j)
            End If
        End If
        For ii = 1 To nnRows
            For jj = 1 To nnCols
                If (Application.CountIf(rgToCheck.Cells(ii, jj), vCriteria) = 1) And (rgToMinMax.Cells(ii, jj).Value <> "") Then
                    If bMinimum Then
                        d = Application.Min(d, rgToMinMax.Cells(ii, jj).Value)
                    Else
                        d = Application.Max(d, rgToMinMax.Cells(ii, jj).Value)
                    End If
                End If
            Next
        Next
        
        If n = 1 Then
            vResults = IIf(Abs(d) = 1E+308, "#None", d)
        Else
            vResults(i, j) = IIf(Abs(d) = 1E+308, "#None", d)
        End If
    Next
Next
MinMaxIf = vResults
End Function

Select allOpen in new window

Brad
MaxIfQ28138002.xlsm

Hi msmax

I opened the file you attached but it is not doing what my original request was.

"I need to put the most recent date in column 'AB' where the numbers in column 'C' are the same"

Below is taken from the spreadsheet attached to your reply.

The result on the below should be 25/2/2013 not 18/07/2011

Reference                        Entry Date      Date Age
148311118      18/07/2011      18/07/2011
148311118      25/02/2013      18/07/2011

The result on the below should be 10/5/2013 not 17/05/2013

Reference       Entry Date      Date Age
903017819      10/05/2013      17/05/2013
903017819      10/05/2013      17/05/2013
903017819      03/05/2013      17/05/2013
903017819      10/05/2013      17/05/2013
903017819      10/05/2013      17/05/2013
903017819      10/05/2013      17/05/2013
903017819      03/05/2013      17/05/2013
903017819      10/05/2013      17/05/2013

Is it possible?

Thanks for that, sorry I was such a dumb ass.