using System;

using System.Collections.Generic;

using System.Linq;

using System.Globalization;

public class Program

{

    public static void Main()

    {

        List<List<string>> _DataCollection = new List<List<string>>

            {

                new List<string> {"tom", "abc", "$525.34", "$123"},

                new List<string> {"dick", "xyz", "$100", "$234"},

                new List<string> {"harry", "", "$250.01", "$40"},

                new List<string> {"bob", "", "$250.01", ""},

            };

​

            decimal _temp =0;

            int ListLength = _DataCollection.First().Count();

            var query = _DataCollection.SelectMany(x => x).

                                       Select((v, i) => new { Val = v, Index = i % ListLength })

                                       .GroupBy(x => x.Index)

                                       .Select(z => z.Sum(y => decimal.TryParse(y.Val,NumberStyles.AllowCurrencySymbol | NumberStyles.AllowDecimalPoint ,new CultureInfo("en-US"),out _temp) ? _temp : 0));

​

            foreach (var result in query)

            {

                if (result == 0)

                    Console.WriteLine("N/A");

                else

                    Console.WriteLine(String.Format("{0:C}",result));

            }

    }

}