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.
Source: National Vital Statistics System
/nchs/data/vsrr/vsrr012-508.pdf
An official website of the United States government
An official website of the United States government