morris.js рисует неверное значение

Я использую morris.js для рисования графика, но он рисует неправильное значение на линейном графике. Всплывающее окно показывает 3, но строка читает 4

Код для рисования графика:

var overviewChart = Morris.Area({
element: 'overviewChart',
  data: $.parseJSON($('#userBlocks').html()),
  xkey: 'y',
  ykeys: ['Blocks', 'Scans'],
  labels: ['Blocks', 'Scans'],
  lineColors: ['#A5C3F7', '#999']
});

Текст проанализирован для данных JSON:

 [{"y":"2014-02-07","Blocks":0,"Scans":0},{"y":"2014-02-08","Blocks":0,"Scans":0},{"y":"2014-02-09","Blocks":0,"Scans":0},{"y":"2014-02-10","Blocks":0,"Scans":0},{"y":"2014-02-11","Blocks":0,"Scans":0},{"y":"2014-02-12","Blocks":0,"Scans":0},{"y":"2014-02-13","Blocks":0,"Scans":0},{"y":"2014-02-14","Blocks":0,"Scans":0},{"y":"2014-02-15","Blocks":0,"Scans":0},{"y":"2014-02-16","Blocks":0,"Scans":0},{"y":"2014-02-17","Blocks":0,"Scans":0},{"y":"2014-02-18","Blocks":0,"Scans":0},{"y":"2014-02-19","Blocks":0,"Scans":0},{"y":"2014-02-20","Blocks":0,"Scans":0},{"y":"2014-02-21","Blocks":0,"Scans":0},{"y":"2014-02-22","Blocks":0,"Scans":0},{"y":"2014-02-23","Blocks":0,"Scans":0},{"y":"2014-02-24","Blocks":0,"Scans":0},{"y":"2014-02-25","Blocks":0,"Scans":0},{"y":"2014-02-26","Blocks":0,"Scans":0},{"y":"2014-02-27","Blocks":0,"Scans":0},{"y":"2014-02-28","Blocks":0,"Scans":0},{"y":"2014-03-01","Blocks":0,"Scans":0},{"y":"2014-03-02","Blocks":0,"Scans":0},{"y":"2014-03-03","Blocks":0,"Scans":0},{"y":"2014-03-04","Blocks":0,"Scans":0},{"y":"2014-03-05","Blocks":0,"Scans":0},{"y":"2014-03-06","Blocks":0,"Scans":0},{"y":"2014-03-07","Blocks":1,"Scans":3}]

Кажется, что серая линия добавляет 3 + 1 = 4 вместо 3. Есть ли способ сделать это всего 3?