'Eighteenth' in the Bible

Joram son of Ahab became king over Israel in Samaria during the eighteenth year of Judah’s King Jehoshaphat and reigned 12 years.

In the eighteenth year of King Josiah, the king sent the court secretary Shaphan son of Azaliah, son of Meshullam, to the Lord’s temple, saying,

But in the eighteenth year of King Josiah, this Passover was observed to the Lord in Jerusalem.