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. 2004 Winter;26(2):73–87.

Table 4. Definition of Variables.

Variable1 Definition/Comment Mean Standard Deviation Minimum Maximum
log(enrollments,t) Log of high-risk pool enrollment. 7.33 1.10 5.16 10.32
log(premiums,t) Log of high-risk pool premium. Only available for 58 observations. 5.39 0.31 4.75 6.05
log(proxy premiums,t)2 Proxy for high-risk pool premimum. 8.89 0.27 8.42 9.68
pct. of market premiums,t High-risk pool premium as percent of market premium. 1.52 0.23 1.18 2
per capita Medicare expenditures,t Used as proxy for market premium. 4,912 924.00 3,139 8,002
lowest deductibles,t Controls for generosity of benefits.3 543.8 235.10 0 1,000
multiple deductibless,t Binary variable; controls for generosity of benefits.3 0.85 0.35 0 1
log(uninsured populations,t) Controls for demand. 12.81 0.78 10.87 14.43
log(per capita family income of uninsureds,t) Controls for demand. 10.46 0.18 10.08 10.86
yeart Controls for trends in enrollment and premiums 1997.58 1.70 1995 2,000
lag log(proxy premiums,t) 2 Used as an additional instrumental variable for log(proxy premiums,t). 8.86 0.27 8.2 9.68
lag pct. of market premiums,t2 Used as an additional instrumental variable for log(proxy premiums,t). 1.52 0.22 1.25 2
lag per capita Medicare expenditures,t2 Used as an additional instrumental variable for log(proxy premiums,t). 4,775 992.00 2,425 8,002
1

Subscript s indexes States (Alabama, Alaska, Arkansas, Colorado, Connecticut, Illinois, Indiana, Iowa, Kansas, Louisiana, Minnesota, Mississippi, Missouri, Montana, Nebraska, New Mexico, North Dakota, Oklahoma, Oregon, South Carolina, Utah, Washington, Wisconsin, and Wyoming). Subscript t indexes years (1995-2000). Not every State has an observation in every year. Three States are excluded: California (enrollment is capped), Florida (pool is closed), and Texas (not in equilibrium).

2

As described in the text, to remove endogeneity, we instrumented for log(proxy premiums, t). The instruments were lag log(proxy premiums, t), lag pct. of market premiums, t, and lag per capita Medicare expenditures,t.

3

Benefits vary by State and year and were not consistently provided in our data sources. Deductible levels, however, were consistently provided and serve as a measure of plan generosity.

NOTE: N=137, except where indicated.

SOURCES: Communicating for Agriculture, Inc.: Comprehensive Health Insurance for High-Risk Individuals (9th-15th editions). Fargo Falls, MN. 2001/2002. U.S. Census Bureau, Current Population Survey (1999-2001).