title: Plotting Time and Groupby Count
body: <p>Hi all sorry if this question seems rudimentary, but I have a table, with the InvoiceDate as the index:</p>
  
  <pre><code>            InvoiceNo | StockCode | Description| Quantity   |  InvoiceDate       | UnitPrice |   Country
  InvoiceDate 536635       85123A          shirt         5        2010-12-01 08:26:00     50      United Kingdom
  </code></pre>
  
  <p>with 390,000 rows, and I have been trying to create a scatter plot/line plot of  month vs a count of the groupby 'description' column. I tried writing this: </p>
  
  <pre><code>df.groupby([df.index.month, 'description']).count().plot()
  </code></pre>
  
  <p>but this returns a bar graph of that returns all columns without time being plotted. Any help would be greatly appreciated!</p>