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.
Data intervals and number of observations for the default options in period selection.
| Selected period | Data intervals | Number of observations |
| 2004 to present | Monthly | >187 |
| Past 5 years | Weekly | 260 |
| Full year (eg, 2004 or 2008) | Weekly | 52 |
| Past 12 months | Weekly | 52 |
| Past 90 days | Daily | 90 |
| Past 30 days | Daily | 30 |
| Past 7 days | Hourly | 168 |
| Past day | 8 min | 180 |
| Past 4 hours | 1 min | 240 |
| Past hour | 1 min | 60 |
