Some systems set up default PINs and most allow the customer to set up a PIN or to change the default one, and on some a change of PIN on first access is mandatory. Customers are usually advised not to set up a PIN based on their or their spouse's birthdays, on driver license numbers, consecutive or repetitive numbers, or some other schemes. Some financial institutions do not give out or permit PINs where all digits are identical (such as 1111, 2222, ...), consecutive (1234, 2345, …), numbers that start with one or more zeroes, or the last four digits of the cardholder's social security number or birth date.