title: Create a method to calculate Linear Interpolation in C#
body: <p>I am tasked to create a method to calculate Liner Interpolation where Y is a DateTime value and X is an integer value.  For example, looking at the following values, how to find the values for 7, 8 and 9?</p>
  
  <pre><code>Date:       Value:
  05/01/2013  5
  06/01/2013  7
  10/01/2013  9
  11/01/2013  1
  15/01/2013  7
  17/01/2013  2
  02/02/2013  8
  
  EDIT: 
  int interpMethod(DateTime x0, int y0, DateTime x1, int y1, int x)
  {
      return y0 * (x - x1) / (x0 - x1) + y1 * (x - x0) / (x1 - x0);
  }
  </code></pre>