st: n-1 variable continuously

[ncdcta00@uniroma2.it]

I have a question about how calculate the number of years work continuously.
I have a panel of 8 year and I want calculated the person how has work  
for 7 years no stop. (1111110)
I used this procedure:
by pid : egen emplo=count(work==1)
here work is=1 if work. after I did the tab emplo and I have the table  
for 8 years.
but there aredifferente sequence how 0111111, or 1011111 ecc and I  
want only 1111110.

for ex: 1011111 but is incorrect
pid   emplo wave  work
1         7  1    1
1         7   3    1
1         7    4   1

How is possible to make it?
thanks


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