'Year of' in the Bible

In the eighth month of the second year of king Darius, came the word of the LORD unto Zechariah the son of Berechiah, the son of Iddo, the Prophet, saying,

Upon the twenty forth day of the eleventh month which is the month Shebat, in the second year of Darius, came the word of the LORD unto Zechariah the son of Berechiah, the son of Iddo, the Prophet, who said,

It happened also in the fourth year of king Darius, that the word of the LORD came unto Zechariah in the fourth day of the ninth month, which is called Chislev.