The number of visits to emergency departments increased by about 20 percent for this group over the seven-year period, from 2.22 million to 2.66 million visits (z=3.18, p<.01). The rate of visits also grew significantly, from 1,162 to 1,314 per 100,000 population (z=2.42, p<.02). As shown in F1, the increase was greatest for patients without insurance, for whom the number of visits grew by about 63 percent (z=5.76, p<.01). In 1999 about 25 percent of visits to the emergency department by adults with a primary mental illness were not covered by insurance, compared with 19 percent in 1993. In contrast, the proportion of general medical visits that were not covered by insurance increased from 15 percent in 1993 to 18 percent in 1999. The number of visits for patients with a primary mental illness that were paid for through private, public (Medicare or Medicaid), or other insurance sources—for example, other state programs—did not significantly change over the study period.