In the hotel industry, we use two terms to describe trade receivables—guest ledger and city ledger. The guest ledger is a list of all outstanding amounts (receivables) owed to the hotel by the guest who did not depart yet, and the city ledger is a list of all outstanding amounts owed by the departed guest who has billing privileges. Usually, the guest ledger is not a challenge for the simple reason that most outstanding amounts will be paid by credit card or cash once the guest checks out. A few accounts will be transferred to the city ledger. Accordingly, most of our efforts are used to control the outstanding receivables in the city ledger. For the same reason, in the hotel business, city ledger and trade receivables are used interchangeably; and the perfect receivables is one that is relatively low in dollars, reasonably current, without a doubt collectable, and ultimately produces no or little write off.