Chart.SetDefaultChart (Word)

Specifies the name of the chart template that Microsoft Word uses when it creates new charts.

SetDefaultChart (Name)

Name: Specifies the name of the default chart template that Word uses when it creates new charts. This name can be set to either the name of a user-defined chart template in the gallery or a special XlChartGallery constant, xlBuiltIn, to specify a built-in chart template.

With ActiveDocument.InlineShapes(1) 
 If .HasChart Then 
 .Chart.SetDefaultChart Name:="Monthly Sales" 
 End If 
End With