How to add a table (change data model) to the EF4 Context without lose of data

Question

I have an MVC3 project I created using the Code First paradigm and it works. I created a model inheriting from DBContext, and I can write to the table and all that. I need to add new table and change my model and I using DropCreateDatabaseIfModelChanges<T> But, I lose all my data, due to EF4 will drop end create new DB.

public class MyDbInitializer : DropCreateDatabaseIfModelChanges< MyDb >

Can I use different interface like UpdateDatabaseIfModelChanges<T> if any exist?

My model looks like this:

[Table("Person")]

public class Person
{
    public int ID { get; set; }
    public string name { get; set; }
    public string country { get; set; }
    public string gender { get; set; }
}

public class MyDb: DbContext
{
    public DbSet<Person> People { get; set; }
}

Then I call:

Database.SetInitializer(new MyDbInitializer ());


public class MyDbInitializer : DropCreateDatabaseIfModelChanges< MyDb >

    {
        protected override void Seed(MyDb context)

And this I want to create:

[Table("Person")]

public class Person
{
    public int ID { get; set; }
    public string name { get; set; }
    public string country { get; set; }
    public string gender { get; set; }
}
[Table("NewTable")]

public class NewTable
{
    public int ID { get; set; }
    public string name { get; set; }
    public string position { get; set; }
    public string description { get; set; }
}


public class MyDb: DbContext
{
    public DbSet<Person> People { get; set; }
    public DbSet< NewTable > NewTable { get; set; }

}