Figure 1.

Trends in opportunity to use and use given opportunity during all seven years of study.

Note. Prescription medication opportunity includes the opportunity to use prescription stimulants, analgesics, and tranquilizers nonmedically. Other drug opportunity includes the opportunity to use inhalants, hallucinogens, cocaine, heroin, and ecstasy. Opportunity to use and use given opportunity values are estimated marginal means. Use given opportunity data are unweighted, and opportunity to use data are weighted to account for sampling design. Opportunity to use and use given opportunity values are not comparable, and the side-by-side presentation is merely meant to compare the shape of trends over time.