I would imagine that a VLOOKUP formula would be easier than a macro in this instance. After filling the formula down the column do a COPY & PASTE.Values to remove the formula.
Edited in VLOOKUP example:
You will need to make a table of the dates in your workbook identical to the dates in the emailed workbook. adjust the following to fit your situation
A1 = is the look up value (date?) from the table where you want the values in the email
[Example.xlsx] = is the name of your emailed workbook
Sheet1! = the name of the spreadsheet in the emailed workbook that has the table of data
$A$1:$B$30 = the complete range of the data in the emailed workbook
2 = the column in the range of data that we want to get the return value from (column 2 in A and B)
FALSE = we want an exact match of the look up value in the email data
=VLOOKUP(A1,[Example.xlsx]Sheet1!$A$1:$B$30,2,FALSE)
However, in order to keep it simple if you are not above keeping one workbook as a template for receiving the data then the following will work. Just place it into a module of the template workbook and save it. When you receive a new email open the template, open the email workbook and then activate the macro from the email workbook
Assumptions in the code:
1: In the emailed workbook the data starts in cell A1
2: In the macro/template workbook the data starts in cell A1
If either of these assumptions are incorrect then adjust the start values for L1 and/or the Cells objects (the first value, L1, is the row and the second number is the column; A = 1)
Sub CopyData()
Dim All As New Collection
Dim One As Variant, L1 As Integer, L2 As Integer
Dim TW As Workbook, EW As Workbook
Set TW = ThisWorkbook
Set EW = ActiveWorkbook
L1 = 15
Do Until Cells(L1, 2).Value = ""
ReDim One(0 To 1)
One(0) = Cells(L1, 2).Value
One(1) = Cells(L1, 3).Value
All.Add One
Erase One
L1 = L1 + 1
Loop
TW.Activate
L1 = 15
Do Until Cells(L1, 2).Value = ""
For L2 = 1 To All.Count
One = All(L2)
If One(0) = Cells(L1, 2).Value Then
Cells(L1, 3).Value = One(1)
Erase One
Exit For
Else
Erase One
End If
Next L2
L1 = L1 + 1
Loop
End Sub