More than 200 million pieces of personal information in South Korea have been leaked either through hacking attacks or poor network management since 2011, a government report showed Thursday.

According to the report by the Korea Communications Commission, more than 200 million cases of private information, such as resident registration numbers, phone numbers and addresses, have been leaked between 2011 and June of this year.

The report released by Rep. Shin Yong-hyeon of the minor opposition People's Party showed that the largest-ever data theft came to light in early 2014 when some 83.58 million cases of client information were leaked from three major card firms -- KB Kookmin Card Co., NH Card Co., and Lotte Card Co