
Overview:
The HHI number can range from close to zero to 10,000. DOJ considers a market with a result of less than 1,000 to be a competitive marketplace; a result of 1,000-1,800 to be a moderately concentrated marketplace; and a result of 1,800 or greater to be a highly concentrated marketplace.

10) Colorado
HMO with the largest market share: Kaiser with 79%
HMO with the second largest market share: Wellpoint with 6%

9) Idaho
HMO with the largest market share: Group Health Cooperative with 80%
HMO with the second largest market share: Intermountain with 15%

8) Nevada
HMO with the largest market share: UnitedHealthcare with 81%
HMO with the second largest market share: Renown Health with 8%

7) North Dakota
HMO with the largest market share: Sanford with 80%
HMO with the second largest market share: Dakotacare with 19%

6) Nebraska
HMO with the largest market share: Kaiser with 79%
HMO with the second largest market share: Wellpoint with 6%

5) Louisiana
HMO with the largest market share: Louisiana Health Service and Indemnity Company (BCBS) with 88%
HMO with the second largest market share: Vantage Health with 5%

4) Utah
HMO with the largest market share: Intermountain with 90%
HMO with the second largest market share: Aetna with 10%

3) South Carolina
HMO with the largest market share: BCBS SC with 91%
HMO with the second largest market share: Aetna with 4%

2) Vermont
HMO with the largest market share: BCBS VT with 94%
HMO with the second largest market share: MVP Health Care with 4%

1) Alabama
HMO with the largest market share: Triton (Viva Health) with 97%
HMO with the second largest market share: UnitedHealthcare with 2%