数组上的挖空子对象具有最后一个项的值

我很困惑，为什么即使我的成分在列表中正确填充并呈现，当我更改例如第一个成分的"剂量参考系统"的值时，它会与剂量参考系统的值混淆数组中最后一项？

不会根据该行中的值进行更新

任何帮助将不胜感激：

这是小提琴：http://jsfiddle.net/makeitmorehuman/C6AvC/

此处供参考的代码是：

function ingredient(data) {
        ingr = this;
        ingr.Name = ko.observable(data.Name);
        ingr.UnitCost = ko.observable(data.UnitCost);
        ingr.DRS = ko.observable(data.DRS);
        ingr.DP = ko.observable(data.DP);
        ingr.PercenChange = ko.computed(function () {
            return Math.round(ingr.DP() - ingr.DRS());
        });
        ingr.RawMaterialRS = ko.computed(function () {              
            return Math.round((ingr.DRS() / 100) * ingr.UnitCost() * 10000);
        });
        ingr.RawMaterialCostProp = ko.computed(function () {
            return Math.round((ingr.DP() / 100) * ingr.UnitCost() * 10000);
        });
        ingr.CostDifference = ko.computed(function () {
            return Math.round(ingr.RawMaterialCostProp() - ingr.RawMaterialRS());
        });
    }
    function ingredientsData() {
        return [
            { "Name": "Skimmed milk", "UnitCost": 0.40, "DRS": 70, "DP": 87 },
            { "Name": "Cream 40% fat", "UnitCost": 1.80, "DRS": 18, "DP": 9 },
            { "Name": "Skim Milk Powder", "UnitCost": 2.5, "DRS": 12, "DP": 1 },
            { "Name": "N-Dulge SAI", "UnitCost": 3.5, "DRS": 0, "DP": 2 },
            { "Name": "Novation Indulge 1720", "UnitCost": 3.9, "DRS": 0, "DP": 1 }
        ];
    }
    function NovationIndulge() {
        var self = this;
        self.Ingredients = ko.observableArray();
        self.init = function () {
            ko.utils.arrayForEach(ingredientsData(), function (item) {
                self.Ingredients.push(new ingredient(item));
            });
        };
        function SumOfItems(propertyToSum) {
            var total = 0;
            ko.utils.arrayForEach(self.Ingredients(), function (item) {
                total = parseInt(total) + parseInt(item[propertyToSum]());
            });
            return total;
        }
        self.TotalDRS = ko.computed(function () { return SumOfItems("DRS"); });
        self.TotalDP = ko.computed(function () { return SumOfItems("DP"); });
        self.TotalCostDiff = ko.computed(function () { return SumOfItems("CostDifference"); });
        self.TotalRawMaterialRS = ko.computed(function () { return SumOfItems("RawMaterialRS"); });
        self.TotalRawMCP = ko.computed(function () { return SumOfItems("RawMaterialCostProp") });
        self.AnnualFinishedProduct = ko.observable(4000);
        self.TotalCostSavingP1000 = ko.computed(function () { return self.TotalCostDiff() * -1 });
        self.TotalAnnualSaving = ko.computed(function () {
            return self.TotalCostSavingP1000() * self.AnnualFinishedProduct() / 1000;
        });
    }
    var NI = new NovationIndulge();
    NI.init();
    ko.applyBindings(NI);