Population Denominator Data for Use with the HCUP Databases

Table A.4.1 Annual Estimates of the U.S. Population by Median Household Income Quartile, 2001 to 2006
Median
Population Estimates
Household
Income Quartile 2001 2002 2003 2004 2005 2006
Quartile 1 70,808,587 74,924,336 69,664,519 76,323,231 72,184,620 74,069,384
Quartile 2 72,417,821 67,591,640 73,559,081 73,175,783 73,179,269 72,324,060
Quartile 3 70,933,564 74,520,370 76,465,150 68,746,327 75,674,376 75,968,161
Quartile 4 69,738,298 69,706,370 70,937,808 74,642,649 74,058,028 75,615,954
Total U.S. 283,898,269 286,742,716 290,626,558 292,887,990 295,096,293 297,977,559
Source: Claritas Population Estimates, 2001 to 2006
Because the cut-points for the median household income quartiles are updated annually, the value ranges for the quartiles vary by year. The dollar
ranges represented by each category are:
Median
Quartile Ranges
Household
Income Quartile 2001 2002 2003 2004 2005 2006
Quartile 1
Quartile 2
1-
33,999
34,000-
43,999
44,000-
58,999
1-
35,999
36,000-
45,999
46,000-
61,999
1-
35,999
36,000-
44,999
45,000-
59,999
1-
35,999
36,000-
44,999
45,000-
58,999
1-
36,999
37,000-
45,999
46,000-
60,999
1-
37,999
38,000-
46,999
47,000-
61,999
Quartile 3
Quartile 4 59,000+ 62,000+ 60,000+ 59,000+ 61,000+ 62,000+
In the HCUP databases, the data element ZIPINC_QRTL contains the median household income quartile, values 1 to 4, for the ZIP Code of the
patient’s residence. The above population data table uses the same definitions of median household income.
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