CENSUS OF POPULATION AND HOUSING, 1990:
                PUERTO RICO REDISTRICTING DATA ON CD-ROM


                           USER NOTE 1


Review of detailed 1990 information indicated that
respondents tended to provide their age as of the date of
completion of the questionnaire, not their age as of April
1, 1990.  In addition, there may have been a tendency for
respondents to round up their age if they were close to
having a birthday.  It is likely that approximately 10
percent of persons in most age groups are actually 1 year
younger.  For most single years of age, the misstatements
are largely offsetting. The problem is most pronounced at
age 0 because persons lost to age 1 may not have been fully
offset by the inclusion of babies born after April 1, 1990
and because there may have been more rounding up to age 1 to
avoid reporting age as 0 years.  (Age in completed months
was not collected for infants under age 1.)

The reporting of age 1 year older than age on April 1, 1990
is likely to have been greater in areas where the census
data were collected later in 1990.  The magnitude of this
problem was much less in the three previous censuses where
age was typically derived from respondent data on year of
birth and quarter of birth.  (For more information on the
design of the age question, see the discussion on
comparability under "Age" in appendix B.)

This user note should be filed in the User Notes Chapter of
the Puerto Rico Redistricting Data.


                                           January 1992