Why StockChartViewController xLabelsSkipLast didn't work?

[SuYungCheng]

Thanks for the useful library first.

I try to use the xLabelsSkipLast method, and want to hide the last label "October".

chart.xLabels = labels
print(labels)      // [0.0, 22.0, 43.0, 64.0]
print(labelsAsString) //["July", "August", "September", "October"]
chart.xLabelsSkipLast = true    // default is true

But there still have the October label, am I misunderstanding?