What does Esther 3:7 mean?

In the first month, the month of Nisan, in King Xerxes' twelfth year, they cast the 'pur' (which means 'lot') in front of Haman to pick a day and month. The lot landed on the twelfth month, Adar. Esther 3:7 - Modern Text Bible

(Haman used lots to choose the date for his plan, which ended up being almost a year away.)