'Eighteenth' in the Bible

In the eighteenth year of King Jeroboam, Abijah reigned over Judah.

Now in the eighteenth year of his reign [after] he purged the land and the house, he sent Shaphan the son of Azaliah, Maaseiah the commander of the city, and Joah the son of Joahaz, the recorder, to repair the house of Yahweh his God.

In the eighteenth year of the reign of Josiah this Passover was kept.