Consider the numbers of community hospital beds per 1000 population
that are available in each state in the U.S. and in the District of
Columbia.  The datasets "bed2.dat" contains these values for both
1980 and 1986. The numbers of beds per 1000 population for both calendar
years are saved under the variable name "bed" and an indicator of year
under the name "year."  There is no information in "bed2.txt" as to which
entries go with which state.

Variables:
    bed
    year