Inferences
We display the number of UFO sightings in US, UK, and other countries from 2001 to 2010. The legend shows which bar represents which country. Since there are many countries in the third group (other countires), the number of UFO sightings is always the highest. We found that most UFO sightings happended in 2003 and 2007 in US. In UK, most of UFO sightings happened in 2009. For other countries, most of UFO sightings happened in 2008.