retain

[Steelers_In_DC]

I am attaching some example code.  I want to find if there was an upsell or downsell over two time periods.  I tried to use a retain statement with by id plan, thinking that it wouldn't retain across id's, that is not the case.  Is retain the right solution for this problem and I have written incorrectly or am I going about this the wrong way.

[art297 · Accepted solution]

data together (drop=diff);

  set jun2014 jul2014;

  by id;

  diff=plan-lag(plan);

  if not first.id then do;

    if diff eq 0 then change = 'none';

    else if diff gt 0 then change = 'up';

    else change = 'down';

  end;

run;

[Steelers_In_DC]

Excellent, thank you.  I looked up a pdf showing retain vs lag but couldn't get what I wanted out of it

thanks,

Mark