/// <summary>
 /// Adjust the interest rate
 /// </summary>
 /// <param name="bankaccount">an instance of bank account</param>
 /// <returns></returns>
 public virtual double RateAdjustment(BankAccount bankAccount)
 {
     return(0);
 }
 /// <summary>
 /// Check if the account state has changed
 /// </summary>
 /// <param name="bankAccount">an instance of bank account</param>
 public virtual void StateChangeCheck(BankAccount bankAccount)
 {
 }
        /// <summary>
        /// Adjust the interest rate
        /// </summary>
        /// <param name="bankAccount">An instance of bank account</param>
        /// <returns></returns>
        public override double RateAdjustment(BankAccount bankAccount)
        {
            double rate = this.Rate;

            return(rate);
        }