. insheet using f:\tt.csv,clear
(5 vars, 486 obs)
. encode id ,gen(id1)
. xtset id1 year
panel variable: id1 (strongly balanced)
time variable: year, 1994 to 2011
delta: 1 unit
. help unitroot
. help unitroot test
. xtunitroot llc cit
Levin-Lin-Chiu test requires strongly balanced data
r(498);