VS 2010 Beta1 "No historical data was collected"

I am trying to use the historical debugger in VS2010 Beta 1.

I turned it on in the settings (at least I think I know), but when I try to examine objects, this value:

[No historical data was collected]

Any ideas how to get this to show the actual value?

Here is the code in question:

 public partial class Form1 : Form

   {

       public Form1()

       {InitializeComponent();}

       private void button1_Click(object sender, EventArgs e)

       {

           int numer = Int32.Parse(txtNumerator.Text) ;

           int denom = Int32.Parse(txtDemoninator.Text);

           float answer = DivideValues(numer, denom);

           txtAnswer.Text = answer.ToString();

       }

       private static float DivideValues(int numer, int denom)

       {

           float answer = numer / denom;

           return answer;

       }

   }