The number of records exposed declined to 267 million compared to 412 million records exposed in 2011.
The number of data breaches has more than doubled to 2,644 incidents in 2012. This is a 117% increase, according to a report by Open Security Foundation and security consultancy Risk Based Security.
"We must exercise caution when analyzing the number of exposed records since on average, 26 percent of the incidents tracked do not report the number of exposed records," said Risk Based Security, CEO Barry Kouns.
Data breaches in the business sector accounted for 60% of total incidents, followed by government (17.9%), Education (12%) and Medical (9.5%).
Nearly 77% of reported incidents were carried out by external agents or activity outside the organisation while 68.2% of incidents were carried out through hacking and was responsible for 22.8% of exposed records in 2012.
Internal data breaches accounted for 19.5% of incidents and 66.7% of exposed records.
The United States accounted for 40% of data breaches.