Look, in the Sky The American Meteor Society maintains a running fireball-tracking system. All reports are analyzed and grouped according to several variables. In 2012, there were 2302 fireball reports, and 590 of these were confirmed by 2-5 witnesses. As of August 2013, there were 507 reports and 142 were confirmed by 2-5 witnesses. Assume the samples are independent.
Is there any evidence to suggest that the proportion of fireball reports that are confirmed by 2-5 witnesses is different for these two time periods? Use a = 0.05.