Number format not working!

Hi

In my model metadata i've using this code to format quantity number with n1 :

public partial class DefaultVisitProductDetailsMetadata
{
        [DisplayName("Drug Name")]
        [Required(ErrorMessage = "{0} Required!")]
        public int? ProductID { get; set; }

        [Column(TypeName = "money")]
        [DisplayName("Drug Quantity")]
        [Required(ErrorMessage = "{0} Required!")]
        [DisplayFormat(ApplyFormatInEditMode = true, DataFormatString = "{0:N1}")] // Not working
        public decimal? Quantity { get; set; }
}

[ModelMetadataType(typeof(DefaultVisitProductDetailsMetadata))]
public partial class DefaultVisitProductDetails
{

}

But it does not works. Here is my view :

@model DefaultVisitProductDetails<div class="row"><div class="col-md-6"><form id="frmEditPackageDetailItem" asp-action="UpdatePackageDetailItem" method="post"><div asp-validation-summary="All" class="text-danger"></div><input type="hidden" asp-for="DefaultVisitProductDetailRowID" value="@Model.DefaultVisitProductDetailRowID" /><input type="hidden" asp-for="DefaultVisitProductHeaderRowID" value="@Model.DefaultVisitProductHeaderRowID" /><div class="form-group"><label asp-for="ProductID" class="control-label"></label><select asp-for="ProductID" class="form-control" asp-items="@ViewBag.ProductID" value="@Model.ProductID"><option></option></select><span asp-validation-for="ProductID" class="text-danger"></span></div><div class="form-group"><label asp-for="Quantity" class="control-label"></label><input asp-for="Quantity" class="form-control" dir="ltr" value="@Model.Quantity" /><span asp-validation-for="Quantity" class="text-danger"></span></div><div class="form-group"><label asp-for="Description" class="control-label"></label><textarea asp-for="Description" class="form-control" value="@Model.Description"></textarea><span asp-validation-for="Description" class="text-danger"></span></div><div class="modal-footer text-right"><button type="button" class="btn btn-default" data-dismiss="modal">Cancel</button><button type="button" id="btnUpdate" class="btn btn-success" onclick="frmEditPackageDetailItem_onSubmitClick()">Save</button></div></form></div></div>

Can anybody help me what's the problem & how to solve it ?

Thanks in advance