'Year of' in the Bible

In the eighth month, in the second year of Darius, the word of the Lord came to Zechariah, the son of Berechiah, the son of Iddo the prophet, saying,

On the twenty-fourth day of the eleventh month, the month Shebat, in the second year of Darius, the word of the Lord came to Zechariah, the son of Berechiah, the son of Iddo the prophet, saying,

And it came about in the fourth year of King Darius, that the word of the Lord came to Zechariah on the fourth day of the ninth month, the month Chislev.