Here's how many U.S. adults were hacked in 2014

An estimated 70 million U.S. adults in 2014 were notified their personal information had been compromised, but only half of them changed their behavior to prevent it from happening again, according to a survey by Consumer Reports.

The 70 million projection is based on a nationally representative survey of more than 3,000 American adults conducted earlier this year, the magazine said.

The non-profit Identity Theft Resource Center said there were 783 known U.S. data breaches in 2014, a 27.5 percent increase over 2013. And while breaches in the medical and health care industry topped the list, that may be because it's one of the few industries required to report such incidents.

Consumers Union, the advocacy branch of Consumer Reports, is backing the passage of Sen. Patrick Leahy's, D-Vermont, proposed Consumer Privacy Protection Act, which would require companies with more than 10,000 customers to notify consumers of a breach within 30 days.

"Congress needs to set strong federal standards for defending consumer data while allowing states to enact or maintain more stringent laws if necessary to protect their residents," said Ellen Bloom, senior director of federal policy and the Washington office for Consumers Union.

A separate report from the Experian credit reporting agency forecasts more pain on the horizon, especially for medical-related leaks. "We expect healthcare breaches will increase -- both due to potential economic gain and digitization of records. Increased movement to electronic medical records, and the introduction of wearable technologies introduced millions of individuals into the healthcare system, and, in return increased, the potential for data breaches," states the 2015 forecast report from Experian's Data Breach Resolution unit.

News headlines have made consumers more aware of the problems as companies such as Target (TGT), Home Depot (HD), Premera Blue Cross, JPMorgan (JPM), eBay (EBAY) and others have been hit by breaches.

Identity Theft Resource Center said the primary cause of data breaches remains hacking, accounting for 22 percent of all publicly identified intrusions over an eight-year period. The second most common cause is "data on the move," which includes storage devices or laptops lost in transit, followed by accidental exposure and subcontractor/third-party breaches.

Consumers Union offers these five tips on how to respond to a data breach notice and guard against fraud and identity theft:

• Accept offers of free credit monitoring services
• Monitor credit and debit card accounts online at least once a week
• Put a security freeze on your files at the three credit reporting agencies
• Heighten your guard against phishing scams
• Change user names and passwords on any accounts you know were breached