Generating lagged variables for panel data

[Marc150]

Is there something special that you have to do to generate lagged variables when using panel data?
When I try the very simple code

'series a=b(-1)' or

'genr a=b(-1)'

the series a ends up having a bunch of missing values, for reasons that I don't understand.

Thanks in advance,
Marc

[EViews Gareth]

No, nothing special. You are doing it correctly

[startz]

Remember that the first observation for each cross-section should be missing.

[Marc150]

Thanks (I've just realized that I was sampling only a subset of observations)

[NeweyWest]

In panel data, if I use series Y=X(-1), many cross-sections have missing data. If I try frml Y=X(-1), the first observation of each cross-section should be missing but it's not.

[startz]

When I try, I get the correct NAs. What version are you using? Can you post a short example?