You can achieve this scenario with two series and numeric axis - the first one will be bar series and the second one point series. The Figure property of the Point series lets you choose from a set of predefined shapes other than the default Ellipse shape (e.g. Cross, Diamond, Circle, Rectangle, Triangle and several different Star marker shapes).
You can find more information about creating a chart with numeric axis in our demo here and a sample demonstrating how to use point series here.
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