Minha lista está nula

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:local="clr-namespace:TestDrive"
             x:Class="TestDrive.MainPage">

    <ListView ItemsSource="{Binding Veiculos}" Margin="25"
              ItemTapped="ListView_OnItemTapped">
        <ListView.ItemTemplate>
            <DataTemplate>
                <ViewCell>
                    <ViewCell.View>
                        <StackLayout Orientation="Horizontal">
                            <Label Text="{Binding Nome}" FontSize="20" 
                                   VerticalTextAlignment="Center">
                            </Label>
                            <Label Text=" - " 
                                   VerticalTextAlignment="Center">
                            </Label>
                            <Label Text="{Binding PrecoFormatado}" FontSize="Bold" 
                                   VerticalTextAlignment="Center">
                            </Label>
                        </StackLayout>
                    </ViewCell.View>
                </ViewCell>
            </DataTemplate>
        </ListView.ItemTemplate>
    </ListView>
</ContentPage>


namespace TestDrive
{
    public class Veiculo
    {
        public string Nome { get; set; }
        public decimal Preco { get; set; }

        public string PrecoFormatado => $"R$ {Preco}";
    }

    public partial class MainPage : ContentPage
    {
        public List<Veiculo> Veiculos { get; set; }

        public MainPage()
        {
            InitializeComponent();

            var mainPage = this;

            mainPage.Veiculos = new List<Veiculo>
            {
                new Veiculo {Nome = "Veloster", Preco = 1000},
                new Veiculo {Nome = "Fusca", Preco = 60000},
                new Veiculo {Nome = "Uno", Preco = 20000}
            };

            BindingContext = mainPage.Veiculos;
        }

Existe alguma restrição do List no Xamarin?