Hello,

Although I searched into the forum could not find a proper answer about setting a research period for DID method around the exogenous shock date. My shock date is 2010 and planning to set research period for DID method two years before and one year after 2010 (comparing 2008, 2009 against 2010, 2011).
Due to another shock happened before 2008, I do not want to include the pre-2008 period in the model in order to protect my analysis from the effects of another shock. But there is no limit for going further in 2011.
So I was wondering whether my research period (2008-2011) is proper according to the above concerns and I will greatly appreciate any reply.

Kind regards,
Cathy