How can I add horizontal lines to a BarPlot

I want to know how could I add Horizontal lines to each bar of a barPlot with different values. I want to let the customer know what is the expected value with an horizo开发者_StackOverflowntal line and what is his real value with a bar.

Any idea ? Thanks

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You can use a second bar plot. Set barBasesVary = YES on the second plot. It will ask the datasource for an additional field called CPTBarPlotFieldBarBase. Return a base value and tip value that will make a short bar.