title: converting zoo to dataframe
body: <p>I converted a <code>zoo time series</code> into a data frame in <code>R</code> and the date became the index of the data frame. Is there a way to have the date represented as a normal column in the data frame?</p>
  
  <pre><code>monthly_df &lt;- data.frame(monthly_zoo)
  
  head(monthly_zoo)
  </code></pre>
  
  <p><img src="https://i.stack.imgur.com/JSb2h.png" alt="zoo output"></p>
  
  <pre><code>head(monthly_df)
  </code></pre>
  
  <p><img src="https://i.stack.imgur.com/DY4ko.png" alt="dataframe output"></p>