public int write(IEnumerable <string> data)
        {
            var dataList = data.Select(c => c.Split(','));
            IEnumerable <DateTime> dates  = dataList.Select(dl => dl[0].ParseToDate());
            IEnumerable <Double>   values = dataList.Select(dl => Double.Parse(dl[1], CultureInfo.InvariantCulture));
            var dateValueDictionary       = new Dictionary <DateTime, Double>();
            // TO test the algorithm
            var extendedDictionary = new Dictionary <DateTime, Double>();
            int index = 0;

            foreach (var value in values)
            {
                dateValueDictionary.Add(dates.ElementAt(index), value);
                index++;
            }
            DateTime tempDate;

            foreach (var keyValue in dateValueDictionary)
            {
                extendedDictionary.Add(keyValue.Key, keyValue.Value);
                _context.Add(new Stock()
                {
                    StockDate = keyValue.Key, StockValue = keyValue.Value
                });
                tempDate = keyValue.Key;
                while (!dateValueDictionary.ContainsKey(tempDate.AddDays(1)) && tempDate < dateValueDictionary.Keys.Last())
                {
                    tempDate = tempDate.AddDays(1);
                    extendedDictionary.Add(tempDate, keyValue.Value);
                    _context.Add(new Stock()
                    {
                        StockDate = tempDate, StockValue = keyValue.Value
                    });
                }
            }

            return(_context.SaveChanges());;
        }