select a.video_id ,round (sum(if(end_time-start_time>=duration,1,0))/count(start_time),3) as avg_comp_play_rate from tb_user_video_log a join tb_video_info b on a.video_id=b.video_id where year(start_time)=2021 group by a.video_id order by avg_comp_play_rate desc