Event Study - How to set up the data?

Hello,

I am currently writing a paper in which I want to study stock recommendations' effect on stock prices.

I have identified all the event dates and downloaded all the stock returns I need into an Excel sheet.

Let's call the event date t=0. I would like to insert 250 returns prior to the event date and 10 returns following the event. That means that I would like to have a series of returns from t=-250 to t=+10, where t=0 is the event date.

As I have many events and because these events happen and different points in time it would take forever to insert them manually.

I have been reading a previous thread http://www.excelforum.com/excel-gene...ent-study.html, regarding a similar problem, but in my case the same company has more than one event, and thus, the formula proposed in that thread doesn't work.

I sincerely hope that someone out there can help.

Cheers