Push values to array in jquery

I have List of items data and empty array quotations :

   var data = {};
   var quotations = [];

I want to fill quotations with data values ,Every time i add new data it added successfully but all data values get last value .

for example :

 $("#addquotation").click(function () {
        debugger;
        var itemname = $("#itemname").val();
        var cost =parseFloat( $("#cost").val());
        var notes = $("#notes").val();
        var date = $("#date").val();


        data.Item = itemname;
        data.Cost = cost;
        data.Notes = notes;
        data.Date = date;

        quotations.push(data);
)};

for first time i add

"test,45,testnotes,2016-02-03" Second time i 've added "test2,45.2,testnotes2,2016-02-05"

when i debug i get data as :

obj(0): "test2,45.2,testnotes2,2016-02-05" obj(1):"test2,45.2,testnotes2,2016-02-05"

it seems it append last version to all data

Please Advice . Thanks