Oxford Economics collated the data using the Gemalto ‘Breach Level Index’, which records all disclosed cyber security breaches to have affected listed firms from 2013 to 2016.
Two-thirds of firms suffered an adverse impact on their share price after being targeted by a cyber breach. Financial services were the worst affected, followed closely by communications firms.
“Financial services experience the greatest burden in terms of impact, reflecting the high levels of regulation, the importance of customer confidence and the potential for financial fraud to be a facet of the breach,” the report said.
Hacking attacks and other breaches of cyber security have hit companies globally in recent years, from U.S. giant Yahoo to U.K. telecommunications firm TalkTalk in 2015.