HighCharts xAxis - tickInterval for month

Question

Am trying to plot spline graph for the no of passed/failed testcases and grouping them based on hour/date/month/year and I am getting this value as irr

Answer 1

What I did was subtracting the date format for month which is m-1. If you have Y,m,d change to Y,m-1,d

This is from php to js