Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
The upper and lower whiskers indicate maximum and minimum range values, respectively (see Table 1 for detailed values). “n.a.” indicates no data available.
