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.
t-statistic plots for site * time interaction in all trackers. Horizontal lines indicate positive and negative critical t-values; Dashed magenta, shoulder; dashed cyan, elbow; dashed grey, wrist; light green, thumb; blue, index finger; orange, middle finger; purple, ring finger; dark green, little finger.
