There were 662 reported data breaches last year, up from 498 in 2009, according to a report from the Identity Theft Resource Center (ITRC).
However, the number of data breaches that took place in 2010 is actually much higher, since not all breaches are reported.
In addition to looking at how many breaches were reported in 2010, the ITRC report also examined what types of data were stolen. Nearly two-thirds of reported breaches involved the theft of Social Security numbers, while 26 percent involved the theft of credit and debit card information. The report also found that more data breaches were the result of theft than human error. Roughly 17 percent of data breaches were the result of hackers breaking into systems, while 15 percent of data breaches were the result of insider thefts. Finally, the report found that nearly 20 percent of data breaches involved the loss of paper documents, while the method that thieves used was unknown in about 38 percent of cases.