st: generate max of past values

[Thomas <thomas.triebs@econ.cam.ac.uk>]

Dear all,

I am trying to get the maximum of all past or present values, i.e.

x[i] = max x[j, j<=i]

I tried the following commands:

bysort id (yr): egen x1 = max(l0.x&l1.x&l3.x), which returns 1 instead 
of the max,
and
bysort id (yr): egen x1 = max(l(0/3).x), which produces an error.

Any idea on how to do this correctly?

Many thanks,

Thomas

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