public void Add(Income income, double amount)
        {
            var costs = Incomes.SingleOrDefault(c => c.Name == income.Name);

            if (costs == null)
            {
                Incomes.Add(income);
            }
            IncomeList.Add(income, amount);
            Save(Incomes);
            Save(new List <IncomeList>()
            {
                IncomeList
            });
        }