In earlier times, different regions used different systems of numbering, not only measures of weight, distance or temperature, but also of time and chronology. In his work “The Easter Computus and the Origins of the Christian Era“, Alden Mosshammer, professor emeritus of history, notes:
The standard chronological reference in many ancient cities was the eponymous year—the name of the chief magistrate who served during that year. Some ancient historians also dated by reference to a numbered Olympiad, beginning with the first Olympic observance, traditionally dated to the summer of 776 BC. Where kings ruled, it was customary to number the years of the monarch. Numbering the years from the foundation of a city or an epochal date in its history was also common. A system of numbering the years by reference to a 15‐year period known as the Indiction, with a base‐date in AD 312/13 emerged in the eastern Empire. Some Christian writers numbered the years from the Creation of the cosmos, others from the Passion of Jesus. Each city had its own calendar, with different names for the month and a different point for the beginning of the year.
https://doi.org/10.1093/acprof:oso/9780199543120.003.0002
In doing so, modern revisionists have discovered that even the numbering systems themselves may have differed in the past: non-positional Roman numbers could have been recorded not only in the decimal style generally accepted today, but also in octal. I have made a simple web application for this kind of research: