Comparing Meta Field date in WPQuery using Meta_Query?

I have dates stored in the format d-m-Y, and i want to display any posts that are in the past, before today.

    $args = array (
        'post_type'=>'property',
        'post_status'=>'publish',
        'posts_per_page'=> 8,
        'paged'=> $paged,
        'meta_query' => array(
            'key' => 'auction_date',
            'value' => date( 'd-m-Y'),
            'compare' => '<',
            'type' => 'DATE'
        ),
      );

This doesn't seem to work and i can't figure out why. Any suggestions would be much appreciated.