Years (winters) are referred to by names, each name consistent across the Realms. Each kingdom or city-state numbers years differently, usually to measure the reign of a dynasty or the current monarch, or since the founding of the country. The result is a hodgepodge of overlapping numbers that serve to confuse the ordinary person and frustrate the sage. The widespread differing year dates include the following:
Dalereckoning (DR): Dalereckoning is taken from the year that humans were first permitted by the Elven Court to settle in the more open regions of the forests. The information within this text is accurate to the close of 1367 DR. In some texts, primarily those which do not have direct ties to Dales history, Dalereckoning is called Freeman's Reckoning (FR).
Cormyr Reckoning (CR): Cormyr Reckoning begins at the foundation of House Obarskyr, the dynasty that still rules that land. The information in this text is accurate to the close of 1342 CR. The 25-year gap between Cormyr Reckoning and Dalereckoning has caused much of the confusion regarding elder days. Timelines and calendars of the period often use DR designators, but place the founding of Cormyr at I DR instead of 26 DR. This is understandable, given that the two reckonings are from two nearby parties and spread by a third (the merchants of Sembia), but it causes learned sages to slam their heads violently against their desks trying to figure things out.
Northreckoning (NR): Used in the City of Waterdeep, Northreckoning dates from the year Ahghairon became the first Lord of Waterdeep. The information within this text is accurate to 335 NR. A more archaic system called Waterdeep Years (WY) dates from the supposed first use of Waterdeep as a trading post. Now largely abandoned except in ancient texts, the current year would be 2455 WY.
Dragon Years (DY): The use of Dragon Years is an ancient form of counting in dragon generations of 200 years each. There are 10 cycles of 200 years to a color, and each two-millenium color is named after a type of dragon. This reckoning is long-since abandoned, such that it is uncertain whether the current year is 145 or 147 of the Adult Red Dragon.
Mulhorand Calendar (MC): One of the oldest calendars in use in the Realms, this ancient scheme of record-keeping dates from the founding of Skuld, the City of Shadows, reputedly by a Mulhorandi god. This tome is accurate to the year 3501 MC.