Hello All, I have data that takes the following form: FUNDNO CUSIP QTR SHARES CHANGE 001 5 2001Q1 100 100 001 5 2001Q2 101 1 001 5 2001Q3 103 2 001 5 2001Q4 103 . 001 5 2005Q1 10 10 001 5 2005Q2 10 . 001 5 2005Q3 11 1 001 5 2005Q4 11 . As you can see, the data is telling me how many shares of a certain stock a fund holds at the end of a quarter (SHARES) and the change since the last period. You can also see that, in 2001Q1 and 2005Q1, the fund initiated its position by buying all of the shares that they owned at the end of the quarter. That is to say, from the data, prior to 2001Q1 and from 2002Q1 to 2005Q1, this fund did not own any of this stock. This infers that, in 2002Q1, this fund sold all 103 shares of this stock, because the next time that this stock shows up, the change in shares is equal to the number of shares held. Meaning that all of that stock was purchased in that quarter. The dataset, however, does not have any entries for when the fund hold none of the stock. So there is no entry for 2002Q1, when I want there to be an entry showing that the fund owns no stock and the change was -103. I also want to retail all the rest of the data that does not change from quarter to quarter. I need figure out how to say the following: If the fund owned a stock at some time in the past, and there is a time when the fund has an equal SHARES and CHANGE value, then the fund must have sold all of this stock after their last report. I have no idea how to do this, but this is really messing up my summary data becuase I am not caputuring any of the liquidation of positions, only the initiation of positions. Let me know if you have any insight. John
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