Millions of earthquakes occur throughout the world each year but most go undetected because they have very small magnitudes or hit remote areas. In the United States, the US Geological Survey National Earthquake Information Center (NEIC) publishes the locations for about 40 earthquakes per day.
Earthquakes caused 664 deaths in 2014, 617 of those in the magnitude 6.1 Ludian Xian, Yunnan, China, event on August 3rd. On August 24th, a magnitude 6.0 earthquake struck in American Canyon, California and one woman died from her injuries 12 days later.
The biggest earthquake in the United States was a magnitude 7.9 event in the Aleutian Islands of Alaska on June 23rd.
To monitor earthquakes worldwide, the USGS NEIC receives data in real-time from about 1,700 stations in more than 90 countries. These stations include the 150-station Global Seismographic Network, which is jointly supported by the USGS and the National Science Foundation, and is operated by the USGS in partnership with the Incorporated Research Institutions for Seismology (IRIS) consortium of universities. Domestically, the USGS partners with 13 regional seismic networks operated by universities that provide detailed coverage for the areas of the country with the highest seismic risk.
In the U.S., 42 of the 50 states, plus Puerto Rico, may experience damaging ground shaking from an earthquake in 50 years, the nominal lifetime of a building.