         let axisSet = graph.axisSet as! CPTXYAxisSet
 
         if let x = axisSet.xAxis {
+            x.delegate = self
+
             x.labelFormatter = xLabelFormatter()
             x.labelTextStyle = TrendViewController.textStyleWhite()
             x.axisLineStyle = TrendViewController.lineStyleThinWhite()


}

extension TrendViewController: CPTBarPlotDataSource, CPTBarPlotDelegate {

    /** @brief @required The number of data points for the plot.
     *  @param plot The plot.

            } else if plotField == .Y {
                return reading.quantity
            }

        }
        return nil
    }
}

// MARK: Axis Delegate Methods
extension TrendViewController: CPTAxisDelegate {

    private func axis(_ axis: CPTAxis,
                      shouldUpdateAxisLabelsAtLocations locations: NSSet!) -> Bool {
