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.
Direct observations (dots) and indirect observations (crosses) for different data sources. The black horizontal lines extend from the midpoint of the observation period to the year of data collection. The UN estimates are plotted as grey circles.
