[DigitalToday reporter Jae-won Choi] A cumulative 260 million people in Japan have had personal information leaked, or face a risk of leakage, due to unauthorised access since April this year, data showed. The figure is more than twice Japan's total population, and related reports surged in October.

Japan's Personal Information Protection Commission on Oct. 28 released the status of personal data leaks and potential leaks from unauthorised access reported between April 1 and Oct. 16, Japanese media outlet ITmedia reported on Oct. 29.

A total of 2,094 cases were reported to the commission. The number of people whose personal information was leaked or potentially leaked was tallied at a cumulative 260 million. That is more than twice Japan's population.

The 260 million figure includes duplicate counts when the same person is included in multiple incidents. It also does not mean all information actually flowed outside, so it differs from the number of actual victims.

Monthly reports rose to 185 in June from 166 in April and 163 in May, then increased to 212 in July and 235 in August. The figure climbed to 303 in September, and reached 830 in October through the 16th. That means reports filed in half a month were 2.7 times the total for all of September.

October reports accounted for about 40 percent of the total. The daily average number of reports was about 52, five times higher than about 10 in September. But the figures are based on report filing dates, not the dates breaches occurred, so they do not mean hacking surged by that amount in October.

There were 41 reports involving more than 1 million people whose data was leaked or at risk of leaking, including 6 reports involving 10 million or more people. There were 310 reports in which the scale could not be determined.

The statistics include only reports submitted directly to the commission by private-sector companies. Reports filed through relevant ministries in sectors such as finance and telecommunications, and reports from public institutions, were excluded. The number of reports may also not match the number of actual incidents because both a contractor and the company that outsourced work may have filed reports on the same incident.

The commission said the figures were provisional and that the number of reports and the number of affected people could change during future investigations and the process of final reporting.