I am having an issue with the gap between separated series of highcharts.
For example, I have a chart with two series. One starts from (1st March 2004) and the other starts from (1st March 2009). They do not overlap each others. When showing on the chart, the barchart automatically zips the time between two chart (skipping the year 2005, 2006...2008) and display 2 time series closing to each others.

Please refer to this for more detail: https://jsfiddle.net/quangvinh910/6vr6dg15/2/
pointStart: Date.UTC(2004, 3, 1),
pointStart: Date.UTC(2009, 3, 1)
How can I show show the full time range between that on the x-axis?