title: How to specify date format when using pandas.to_csv to YYYY-MM-DD?
body: <p>The OP of <a href="https://stackoverflow.com/questions/13999850/how-to-specify-date-format-when-using-pandas-to-csv">this post</a> highlighted the lack of documentation for using the date_format argument in pandas. I would like to format the data into YYYY-MM-DD, not MM/DD/YYYY when using the to_csv command.</p>
  
  <p>I've tried: <code>frame.to_csv(output_dir, index=False, encoding='utf-8', date_format='%Y-%m-%d')</code> and it is not working, where frame is a DataFrame</p>
  
  <p>The file I'm trying to convert can be found <a href="http://www.filedropper.com/job0104" rel="nofollow noreferrer">here</a></p>