The Impact of Access Regulation on Health Insurance Market Structure. Table 9: Descriptive Statistics: Group Market, 1995-1997 (N=150)

10/20/2000

  Mean Maximum Minimum Standard deviation
Population (in millions) 4.63 29.40 0.42 5.16
Number of insurers 48.57 94 13 20.56
Top five market share 0.7080 0.9700 0.3780 0.1463
Herfindahl index 0.2089 0.8645 0.0480 0.1529
Average loss ratio 0.79 0.94 0.51 0.63
Guaranteed issue - all products 0.2533 1 0 0.4364
Guaranteed issue - some products 0.4200 1 0 0.4952
Guaranteed issue - some or all products 0.67 1 0 0.47
Guaranteed renewal 0.9133 1 0 0.2823
Health rate band 0.5975 1 0 0.2894
Age rate band 0.1165 1 0 0.2269
Composite rate band 0.1449 1 0 0.2502
Waiting period (in months) 16.98 72 0 19.30
Any limit on preexisting condition exclusions 0.8933 1 0 0.3097
BCBS market share 0.4195 0.9295 0.0677 0.1927
Commercial market share 0.2188 0.6553 0.0352 0.1124
HMO market share 0.3617 0.7317 0.0000 0.1830