How to get a value from this year minus last year.

[pacruz]

I have a data set that calculates trade deficit in various years. I need to calculate the trade deficit between the last year of the data set and the second to last year of the data set. Please advise,

[nehalsanghvi]

Please provide a sample of the dataset preferably in data step code form that we can run. generate and then try out a solution for you.

[RW9]

YRDIFF() function can get years between 2 dates.  If you want good answers then provide the required information, we can't see anything about what your tring to do, so post test data in the form of a datastep and required output and any other information.

[pacruz]

Thank you!

[art297]

If you just need to calculate the change (delta) of the most recent two years of your data per company, then you could use something like:

data have;
  set sashelp.class (rename=(sex=company height=deficit weight=year));
run;

proc sort data=have;
  by company  descending year;
run;

data want (keep=company delta);
  set have;
  by company;
  retain hold_deficit;
  if first.company then do;
    counter=1;
    hold_deficit=deficit;
  end;
  else do;
    counter+1;
    if counter eq 2 then do;
      delta=hold_deficit/deficit-1;
      output;
    end;
  end;
run;

Art, CEO, AnalystFinder.com

[Astounding · Accepted solution]

So that's really all that is involved?  No third variable like COUNTRY?  If you are only concerned with that single difference, here is a way to add it onto the final observation:

proc sort data=have;

by year;

run;

data want;

set have end=done;

deficit_diff = diff(deficit);

if done=0 then deficit_diff=.;

run;

This program calculates the deficit difference on every pair of observations, then wipes out the calculated value for all but the final pair of years.