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.
Notes: Kernel (regression line) is a weighted local polynomial smooth regression. CI = confidence interval. The thick vertical line indicates the date of the OC leaving. The thin lines indicate structural breaks.
