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 160 distributions resulted from pooling linearly or logarithmically. The dotted line indicates the median and the shaded error indicates the interquartile range.
