The data describes a selection of the largest online data breaches worldwide as of March 2018, ranked by number of records stolen. In August 2016, a 2014 hack of online platform Yahoo was uncovered, affecting at least 500 million users accounts. In December 2016, the company revealed another hack dating back to 2013, which affected 1 billion user records. The impact of the second reported Yahoo hack was updated in October 2017, when the company revealed that 3 billion accounts had been affected, making it the biggest data breach in history.
