 
     _combineDailyTimes: (dailyTimes...) ->
       combined = {}
-      for date in  _.union (_.map dailyTimes, _.keys)
+      for date in  _.union.apply _, (_.map dailyTimes, _.keys)
         combined[date] = 0
         for dailyTime in dailyTimes
           combined[date] += dailyTime[date] ? 0
       combined
+
     _addTimeToRow: (row, time, day) ->
       @transformRowData row.id, "rowTotalTime", (current) ->
         (current ? 0) + time

    getRowData: (id, keytype) ->
      key = "#{id}:#{keytype}"
      @api.getData key
    setRowData: (id, keytype, value) ->
      key = "#{id}:#{keytype}"
      @api.setData key, value
    transformRowData: (id, keytype, transform) ->
      @setRowData id, keytype, (transform (@getRowData id, keytype))


        dailyTime[key] = (dailyTime[key] ? 0) + period.time
      @setRowData row.id, "rowTotalTime", totalTime
      @setRowData row.id, "rowDailyTime", dailyTime

    _addTimeToAncestors: (row, time, day) ->
      for ancestorId in @api.view.data.allAncestors row.id, { inclusive: true }
        @transformRowData ancestorId, "treeTotalTime", (current) ->
