javascript 获取最近12个月

编写一个javascript函数，返回一个数组，其中包含了最近12月：

//Make some functions as tools
//return array
function getLast12Months(){
	var last12Months = [];
	var today = new Date();
	
	today.setMonth(today.getMonth()+1);
	for(var i=0;i<12;i++){
		var lastMonth = today.setMonth(today.getMonth()-1);
		last12Months[11-i] = today.getFullYear() + "-" + fillZero((Number(today.getMonth())+1),2);
	}
	return last12Months;
}

结果的形式如下：

[ '2013-05',  '2013-06',  '2013-07',  '2013-08', ....]