title: Select count by datetime
body: <p>How can I select the current row count of the table until the current month, and to group count values by last 6 months?</p>
  
  <p>Sample data:</p>
  
  <pre><code>Id     CreatedTime      PersonId       MonthValue
  1      2015-03-01       1              100
  2      2015-03-15       5              200 
  3      2015-04-19       7              400 
  ...
  ...
  ...
  980    2016-07-22       1349           100
  </code></pre>
  
  <p>Wish to group row count in output like:</p>
  
  <pre><code>Date       Total
  07/2016    331
  06/2016    277
  05/2016    145
  04/2016    100    
  03/2016    69
  02/2016    57
  </code></pre>