Hi there

Any advice on an easy way to code the following would be greatly appreciated.

Code:
clear
input float(year1 year2 year3 year4)
0 0 0 1
0 1 0 1
1 0 1 0
1 0 0 1
0 1 0 0
1 0 0 0
0 0 1 0
end
For each observation, if a later year is flagged 1, I want every previous year to be flagged 1 as well.

I hope that makes sense.

With thanks