Diwali holidays

As per calendar 18th October is diwali here in tamilnadu. But in list of trading holidays its only 19th October. So cant we get holiday for diwali?

Entire India follows one calender only. No state specific holidays except Maharashtra due location of Exchange.

Non trading related question
Anyone know why diwali day is different for north and south india


That is due difference in Tamil calender with other languages. New Year date is different in Tamil calender but most of the states it is same and comes 15 days earlier. Each state calls it different Name.

Deepavali comes on Karthika Amavasya ( New Moon Day). Duration of the New Moon period some times falls on two days so it may interpreted differently.

Deepavali means Series of Lights.