HoldingValue ComputeTotalStockValue(string user, string password)
        {
            Token      token  = AuthService.Check(user, password);
            Holdings   stocks = DbService.GetStockHoldings(token);
            StockRates rates  = StockService.GetRates(token);

            return(ProcessStocks(stocks, rates));
        }
 private HoldingValue ProcessStocks(Holdings stocks, StockRates rates)
 {
     throw new NotImplementedException();
 }