Since the beginning of the 20th century, shark attacks on human populations have increased considerably. The total 98 unprovoked attacks confirmed in 2015 is the highest on record, surpassing the previous high of 88 attacks recorded in 2000. According to the International Shark Attack File - the only globally-comprehensive, scientific shark attack database in the world - the most attractive terrains globally for attacks are coastal areas of the United States, Brazil, South Africa, and Australia.
In 2015, 164 total shark attacks were confirmed worldwide. Sixty percent (98 attacks) were unprovoked attacks. A majority of the other shark attacks were either provoked (36 attacks) or occurred between a shark and a vessel (14 attacks), with a handful of cases attributed to sunken ships or downed aircraft, known a "air-sea disaster," or post-mortem bites, referred to as "scavenge" attacks. Some cases were inevitably indeterminate, if there was insufficient original evidence available to verify a shark attack, or misclassified as shark attacks when the incidents were actually attributable to other or unknown marine life.
As shark attacks become more common, the delicate coexistence of humans and sharks in popular offshore areas is in the balance. Multiple factors have contributed through time to the number of recorded attacks and could help to inform warnings for coastal areas.