title: Date List Not Counting Current Month
body: <p>I am trying to make a date list like this:</p>
  
  <pre><code>date_list
  Out[27]: 
  ['Sep 2014',
   'Oct 2014',
   'Nov 2014',
   'Dec 2014',
   'Jan 2015',
   'Feb 2015',
   'Mar 2015',
   'Apr 2015',
   'May 2015',
   'Jun 2015',
   'Jul 2015',
   'Aug 2015']
  </code></pre>
  
  <p>But for some reason my code is cutting out August. I take a chunk of code from the last year until now. </p>
  
  <p>I made an if statement because if it was the last day of the month it would only take 11 of the last months rather than 12.</p>
  
  <pre><code>range_max = datetime.datetime.now() 
  date = datetime.datetime.now()
  
  if datetime.datetime.now().day == calendar.monthrange(date.year, date.month)[1]:
      range_min = range_max - pd.tseries.offsets.DateOffset(years=1)+ pd.tseries.offsets.DateOffset(days=1)
  else:
      range_min = range_max - pd.tseries.offsets.DateOffset(years=1)+ pd.tseries.offsets.MonthEnd(1) + pd.tseries.offsets.DateOffset(days=1)
  </code></pre>
  
  <p>Then I take the slice out of the data frame</p>
  
  <pre><code>df = df[(df['recvd_dttm'] &gt;= range_min) &amp; 
                 (df['recvd_dttm'] &lt;= range_max)]
  </code></pre>
  
  <p>Then I make my date_list.    </p>
  
  <pre><code>date_list = pd.DataFrame(index=pd.date_range(start = range_min, end = range_max, freq='M'))
  print date_list
  date_list = date_list.index.to_series().apply(lambda x: datetime.datetime.strftime(x, '%b %Y')).tolist()
  </code></pre>
  
  <p>However, this is printing</p>
  
  <pre><code>date_list
  Out[27]: 
  ['Sep 2014',
   'Oct 2014',
   'Nov 2014',
   'Dec 2014',
   'Jan 2015',
   'Feb 2015',
   'Mar 2015',
   'Apr 2015',
   'May 2015',
   'Jun 2015',
   'Jul 2015']
  </code></pre>
  
  <p>Does anyone know why it's not calling August data? This was just working the other day, I don't understand what's gone wrong. The August data is definitely in the data frame I am pulling for this code. </p>