I would like to know whether the CPS data of the years 1985 - 1991 has been treated in any way since 1995. Has there been any harmonization or other changes to CPS data, i.e. when data was made accessible on the database? I have worked extensively on CPS data of the period 1985 - 1991 and summary statistics (such as age of respondends in the sample) in my data set are different from the summary statistics presented in a paper published in 1996 – this paper uses CPS data, yet it appears likely that back then CPS data was only accessible in a different format. Having ruled out other factors (with high degree of certainty) that could explain the differences I noted, I am looking for a clue concerning the history of CPS data. I would appreciate any hint as to where I can find information on how CPS data was made accessible in the mid-1990s (if that is different from today) and – most importantly – whether this could explain differences in summary statistics such as age.