Take a look at this. It allows you to link the Excel data range (or chart) to PowerPoint. Just right-click the image in PPT and select Update Link.
VBA code to Paste Link into PPT
Then, consider the following for adjusting the chart colors in Excel prior to using the above:
Sub ColorCompChart()
Dim i As Long
Dim myComp As String
Dim myRow As Integer
Dim myCol As Integer
If ActiveChart Is Nothing Then
InputBox "Select Chart"
Exit Sub
End If
With ActiveChart
With ActiveChart.SeriesCollection(1)
myRow = InputBox("What is row number")
myCol = InputBox("What is column number?")
For i = 1 To 7
myComp = ActiveSheet.Cells(myRow - 1 + i, myCol).Value
Select Case myComp
Case "CompA"
.Points(i).Interior.ColorIndex = 33
Case "CompB"
.Points(i).Interior.ColorIndex = 40
Case "CompC"
.Points(i).Interior.ColorIndex = 6
Case "CompD"
.Points(i).Interior.ColorIndex = 3
Case "CompE"
.Points(i).Interior.ColorIndex = 26
Case "CompF"
.Points(i).Interior.ColorIndex = 1
Case "Other"
.Points(i).Interior.ColorIndex = 17
End Select
Next i
End With
End With
End Sub
Note: the two InputBoxes ask for numbers of the upper left cell of the data set (not the title row). Thus, if you have column headings in row 1, and data that begins in D2, the Row number would be 2, and the column number would be 4. If the heading is in H6, then the row number is 7, and column number is 8.