title: How to create a variable of rownames?
body: <p>I have an object in R that looks like this:  </p>
  
  <pre><code>                 returns   
  2010-1-4    -0.015933327              
  2010-1-11   -0.015042868    
  2010-1-18    0.005350297  
  2010-1-25   -0.049324703    
  2010-2-1    -0.052674121  
  </code></pre>
  
  <p>I want to make it into:</p>
  
  <pre><code>        date       returns             
  1 2010-01-04 -0.0159333272          
  2 2010-01-11 -0.0150428685        
  3 2010-01-18  0.0053502965        
  4 2010-01-25 -0.0493247026       
  5 2010-02-01 -0.0526741206        
  </code></pre>
  
  <p>How can I do this?</p>