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.
Each box-plot shows median (middle red line) together with its 95% confidence interval (notches). The lower and upper edge indicate 25
and 75
quantile, the whiskers show the span the data.
