st: creating a "years since event" variable in panel data

[Christer Thrane <lineea@broadpark.no>]

Hi,

I have a annual panel data set (1 obs per year), where ID identifies the 
person and the variable OBSYEAR the year of observation (1995=1, 1996=2, 
..., 2002=7).

The variable TIME is the time dimension, ranging from 0 to 7.

The variable EVENT is a dymmy (1=event happened during the year in question; 
0=event did not happen during the year in question).

Q: How do I create the variable NUMBER OF YEARS SINCE (A POSSIBLE) CHANGE 
FROM 0 to 1 on EVENT?

Best regards,

Christer Thrane 
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