Вчерашние свечи в CandleManager

using Ecng.Trading.Algo.Candles;
using Ecng.Trading.BusinessEntities;
using Ecng.Trading.Quik;

public class CandleHistoryManager : CandleManager
{
private CultureInfo _culture;
private IEnumerable<TimeFrameCandle> _history;
public CandleHistoryManager(QuikTrader Quik)
: base(Quik)
{
_culture = new CultureInfo(System.Threading.Thread.CurrentThread.CurrentCulture.Name) { NumberFormat = { NumberDecimalSeparator = "." } };

}

public IEnumerable<TimeFrameCandle> GetTimeFrameCandlesHistory(Security security, TimeSpan timeframe, int candleCount)
{
var candleList = base.GetTimeFrameCandles(security, timeframe, candleCount).ToList<TimeFrameCandle>();
if (candleList.Count < candleCount)
{
int diff = candleCount - candleList.Count;
string fileName = String.Format("{0}.txt", security.Id);
if (!File.Exists(fileName))
{
return candleList;
}
if (_history == null)
{
_history = File.ReadAllLines(fileName).Select(line =>
{
var parts = line.Split(',');
var time = DateTime.ParseExact(parts[0] + parts[1], "yyyyMMddHHmmss", _culture);
return new TimeFrameCandle
{
OpenPrice = double.Parse(parts[2], _culture),
HighPrice = double.Parse(parts[3], _culture),
LowPrice = double.Parse(parts[4], _culture),
ClosePrice = double.Parse(parts[5], _culture),
TimeFrame = timeframe,
Time = time,
TotalVolume = int.Parse(parts[6], _culture),
Security = security
};
});
}
var neededRange = _history.OrderBy(key => key.Time).ToList<TimeFrameCandle>().GetRange((_history.Count() - diff), diff);
candleList.InsertRange(0, neededRange);
}
return candleList;
}