Cybercrime claimed as many as 23 million victims in Germany over the course of 2017, equivalent to some 38 percent of all adults who are regularly online, the U.S. computer security company Norton by Symantec said on Tuesday.

The company put the total damage caused at almost 2.2 billion euros ($2.7 billion).

Identity theft, followed by attacks with ransom software and credit card fraud, were the main crimes, Norton said.

The company undertakes an annual study of cybercrime, taking in 20 countries in 2017. Worldwide, 978 million users suffered criminal damage.

The study found "astonishing parallels" in the victims, most of whom were average uses who were relatively skilled, but showed "a certain carelessness" when online.

"Many people behave with dangerous carelessness," Norton manager Nick Shaw said.

According to the study, 7 percent of German users were hit by ransomware, where their own data are blocked and a ransom is demanded its release.

According to Norton, around one in 10 of these victims paid up. Norton advises computer users to back up their data.

"Giving in to the demands of hackers merely helps the attackers," he said, while there was no guarantee that the data would be restored.