title: how to count the number of lines in a text file that start with a date
body: <p>I have a file that has the content as</p>
  
  <pre><code>2004-10-07     cva        create file ...
  2003-11-11     cva        create version ...
  2003-11-11     cva        create version ...
  2003-11-11     cva        create branch ...
  </code></pre>
  
  <p>now I want to count the number of lines that start with date in this particular file.
  How can I do that</p>
  
  <p>if I use <code>wc -l &lt;file.txt&gt;</code><br>
  it gives me total number of lines(5 in my case whereas I want is count should be 4)</p>