Backbone confusion

gistfile1.txt

var test = Backbone.Model.extend({
	var1 : [],

	initialize : function(obj) {
		this.var1.push("1")
		console.log(this.var1.length, this.cid)
	}
});

var x = (new test);
var y = (new test);

1 "c37"
2 "c38"

//expecting length of 1 each time


var test = Backbone.Model.extend({
	var1 : [],

	initialize : function(obj) {
		this.var1.push("1")
		console.log(this.var1.length, this.cid)
	}
});

var x = new test()
var y = new test()
1 "c39"
2 "c40"