Put this code in the module for the sheet containing the data. If your data is in A:B, the output will be in D:E.
Private Sub Averages()
Dim ReadRow As Long ' row
Dim WriteRow As Long
ReadRow = 2
WriteRow = 2
Do Until Cells(ReadRow, "A") = ""
If Application.WorksheetFunction.CountIf(Range(Cells(2, "A"), Cells(ReadRow, "A")), Cells(ReadRow, "A")) = 1 Then
Cells(WriteRow, "D") = Cells(ReadRow, "A")
Cells(WriteRow, "E") = Application.WorksheetFunction.AverageIf(Range("A:A"), Cells(ReadRow, "A"), Range("B:B"))
WriteRow = WriteRow + 1
End If
ReadRow = ReadRow + 1
Loop
End Sub