2 Kings 15:30

30Then Hoshea, the son of Elah, conspired and carried out treachery against Pekah, the son of Remaliah. And he struck him, and killed him. And he reigned in his place, in the twentieth year of Jotham, the son of Uzziah.
15:30 In the twentieth year of Joatham: That is, in the twentieth year, from the beginning of Joatham’s reign. The sacred writer chooses rather to follow here this date than to speak of the years of Achaz, who had not yet been mentioned.(Challoner)
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