To set the month value using Universal Coordinated Time (UTC), use the setUTCMonth method.
If the value of numMonth is greater than 11 (January is month 0) or is a negative number, the stored year is modified accordingly. For example, if the stored date is "Jan 5, 1996" and setMonth(14) is called, the date is changed to "Mar 5, 1997."
The setFullYear method can be used to set the year, month, and day of the month.
var d, s; //Declare variables.
d = new Date(); //Create Date object.
d.setMonth(newmonth); //Set month.
s = "Current setting is ";
s += d.toLocaleString();
return(s); //Return new setting.