text: # Write your MySQL query statement below
  
  select t.Request_at as Day, ifnull(round(t2.Cancellation / count(*), 2), 0.00) as "Cancellation Rate"
  from Trips t
  left join Users c on t.Client_id = c.Users_Id and c.Banned = "No"
  left join Users d on t.Driver_id = d.Users_Id and d.Banned = "No"
  left join (
      select t1.Request_at, count(*) as Cancellation
      from Trips t1
      left join Users c on t1.Client_id = c.Users_Id and c.Banned = "No"
      left join Users d on t1.Driver_id = d.Users_Id and d.Banned = "No"
      where
      t1.Request_at between "2013-10-01" and "2013-10-03"
      and t1.Status != "completed"
      and c.Users_Id is not null
      and d.Users_Id is not null
      group by t1.Request_at
  ) as t2 on t.Request_at = t2.Request_at
  where
  t.Request_at between "2013-10-01" and "2013-10-03"
  and c.Users_Id is not null
  and d.Users_Id is not null
  group by t.Request_at
  order by t.Request_at
  ;
  