Data: Congressional Budget Office based on data from Kaiser Family Foundation and Health Research and Educational Trust, Employer Health Benefits: 2009 Annual Survey (Washington, D.C.: Kaiser/HRET, 2009), Exhibit 9.4.
Note: Tier 1 (generic) drugs are copies of brand-name drugs whose patents have expired and that therefore may be produced and distributed by multiple drug companies. Tier 2 (preferred) drugs are brand-name drugs that typically are still protected by patents and therefore have no generic substitute. Tier 3 (nonpreferred) drugs are brand-name drugs that typically have a generic substitute.
Source: Congressional Budget Office.
