count rows given same value in one column

foreach (DataRow row in dt.Rows)
{
   var nameCo = from c in dt.AsEnumerable()
                group c by c.Field<string>("yName") into g
                 select new
                 {
                   Name = g.Key,
                   List = g.ToList(),
                 } into g
                 select new
                 {
                   g.Name,
                   Count = g.List.Count,
                   durAve = g.List.Average(x => x.Field<int>("Duration")),
                   durMax = g.List.Max(y => y.Field<int>("Duration"))
                 };
        foreach (var summary in nameCo)
        {
          Console.WriteLine("Name:" + summary.Name.ToString() + ", Volume:" +  summary.Count.ToString() + ",Average:" + summary.durAve.ToString() + "Longest duration: " + summary.durMax.ToString());
        }