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It is possible to have two y-axis visible in the same plot. This can be done by having multiple timeseries where some are assigned to the left y axis and some to the right y axis, or by having a timeseries on the left y axis with an assigned rating curve on the right y axis. So every timeseries plot (also in reports) will have a mandatory left y axis to which a timeseries is assigned and an optional right y axis to which a timeseries or rating curve is assigned.
Both left y axis and right y axis can be customized using <leftAxis> and <rightAxis> configuration elements. Note that <leftAxis> configuration is used only if at least one time series is attached to the left axis. The same goes for the <rightAxis>.
The display of threshold lines are supported for one y axis. But there can be threshold lines for either the left or the right y axis, but not both. Note that further constraints on what thresholds are displayed is possible in the reports schema.
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