I recorded a macro and then 'played' with it
This seems to work

Sub Macro2()
'
' Macro2 Macro
' Macro recorded 27/10/2006 by Bernard V Liengme
'

'
ActiveSheet.ChartObjects("Chart 1").Activate
ActiveChart.ChartTitle.Select
t1len = Len(Range("Sheet1!title1"))
t2len = Len(Range("Sheet1!title2"))
With Selection.Characters(Start:=1, Length:=t1len).Font
.Size = 18
End With
Selection.AutoScaleFont = False
With Selection.Characters(Start:=t1len + 1, Length:=1).Font
.Size = 4
End With
Selection.AutoScaleFont = False
With Selection.Characters(Start:=t1len + 2, Length:=t2len).Font
.Size = 14
End With
ActiveChart.ChartArea.Select
End Sub

best wishes
--
Bernard V Liengme
www.stfx.ca/people/bliengme
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