[Solved]-High Chart X Axis to display month and year-Highcharts

Try this :

xAxis: {
    type: 'datetime',          
    labels: {
        formatter: function() {
             return Highcharts.dateFormat('%b-%Y', this.value);
        }
    }
},

From the docs:

%b - Abbreviated month name, based on the locale(Jan through Dec)

%Y - Four digit representation for the year(Example: 2038)