 
 class TrendViewController : UIViewController {
 
+    static let minutesPerWeek = Double(MINUTES_IN_ONE_HOUR * HOURS_IN_ONE_DAY * DAYS_IN_ONE_WEEK)
+
     var trendsAlgorithmModel: TrendsAlgorithmModel?
 
     private var scatterGraph : CPTXYGraph? = nil

            x.axisLineStyle = TrendViewController.lineStyleThinWhite()
            x.majorTickLineStyle = TrendViewController.lineStyleThinWhite()
            x.minorTickLineStyle = TrendViewController.lineStyleThinWhite()
            x.majorIntervalLength   = 50000
            // x axis located at y coordinate == x.orthogonalPosition
            x.orthogonalPosition    = 0.0
            x.minorTicksPerInterval = 0
            x.labelExclusionRanges  = [
                //CPTPlotRange(location: 0.99, length: 0.02),
                //CPTPlotRange(location: 1.99, length: 0.02),

        guard let dateLast = trendsAlgorithmModel?.ha1cArrayReadingLast()?.timeStamp else {
            return rangeEmpty
        }
        let minutesLastMinusFirst = dateLast.timeIntervalSince(dateFirst) / Double(SECONDS_IN_ONE_MINUTE)
        let location = minutesLastMinusFirst - minutesPerWeek
        let range = CPTPlotRange(location: NSNumber(value:location), length: NSNumber(value: minutesPerWeek))
