   bandWidth = 350
   valueFormat = formatMagnitudeLong
   interval = d3.time.year
+  labelAttr = "key"
 
   title = ""
   eventListeners = {}



        for d in data
          t = Math.ceil(tscale(d.date))
          v = d.value
          
          [band, limits] = valueToBand(v)

        .datum(purposes)
        .call(purposesChart)


      loadingFinished()

