I interpret this as meaning that you have time series data with
regularly spaced observations. If that's not true, what follows will
need modification. 
You need a weighted mean of an expression that would produce an
indicator variable. David Kantor's _gwtmean function for -egen- from SSC
will do that, but I don't know a command that will do this without
generating a new variable, but it's programmable. 
Nick 
[email protected] 
Howard Lempel
Is there a command that will give me the proportion of the time a
variable is equal to a certain value?  The command must accept weights.
I'm looking for something like -tabcond-, from SSC, but that returns
proportions as well as counts.
One option would be to -generate- a dummy equal to 1 when my variable is
equal to my value and zero otherwise and then to use -svy: mean-, but I
would prefer something that can be done in one line (and without
generating a new variable).  My variable is continuous, so I don't want
to -svy: tab- the whole thing.
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