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 dotted line indicates 95% filtration efficiency; circles, outliers, edges of boxes, upper and lower quartiles; center line in boxes, median value; whiskers, the minimum and maximum values.
