'Year of' in the Bible

From the Hebronites: Jerijah was the head of the Hebronites, according to the genealogical records of his ancestors. A search was made in the fortieth year of David’s reign and strong, capable men were found among them at Jazer in Gilead.

Now the children of Israel after their number, to wit , the heads of fathers houses and the captains of thousands and of hundreds, and their officers that served the king, in any matter of the courses which came in and went out month by month throughout all the months of the year-of every course were twenty and four thousand.