December (Roman month) "(VII Kal. Ian." on the pre-Julian calendar, when December had only 29 days). On the calendar of the Roman Republic and early Principate, each day was marked with a letter to denote its religiously lawful status. By the late 2nd century AD, extant calendars no longer show days marked with these letters, probably in part as a result of calendar reforms undertaken by Marcus Aurelius. Days were also marked with nundinal letters in cycles of "A B C D E F G H", to mark the "market week" December (Roman month) December (from Latin "decem", "ten") or mensis December was
Delivery month futures exchanges (such as bonds, short-term interest rates, foreign exchange and US stock indexes) tend to expire quarterly, in March, June, September and December. For financial contracts traded on non-US futures exchanges, the expiration schedule may not be quarterly. This table lists the conventional letter codes used in tickers to specify delivery month: To name a specific contract in a financial futures market, the month code will follow the contract code, and in turn be followed by the year. For example, CLZ3 is the December 2023 NYMEX crude oil contract. CL denotes crude oil (crude light), Z corresponds to the