from t in dbContext.TrackerRecords
   where t.DeviceSerial.Value.Equals(deviceSerial) &&
   t.Date.Value >= fromDate && t.Date.Value <= toDate
   orderby t.Date.Value descending
   group t by t.Date.Value.Date into g
   select new TripDataModel
   {
      Day = g.Key,
      Trips = (from x in g
         group x by x.Date.Value.Hour into gj
         where gj.Max(m => m.Speed.Value) > 0
         let AvgSpd = gj.Average(m => m.Speed.Value)
         select new TripModel
         {
            MinSpeed = gj.Min(m => m.Speed.Value),
            MaxSpeed = gj.Max(m => m.Speed.Value),
            AvgSpeed = AvgSpd > 0 ? Math.Round(AvgSpd, 2, MidpointRounding.AwayFromZero) : 0,
            FromHour = new DateTime(g.Key.Year, g.Key.Month, g.Key.Day, gj.Key, 0, 0)
         })
   }

from t in dbContext.TrackerRecords.ToList()