In 2007, the average total cost of a breach for a company in any industry was $6.3 million, said the Ponemon Institute, which surveyed 35 companies across all industries who experienced a data breach this year.

Costs ranged from $225,000 per breach to almost $35 million. The average cost of each compromised record was $197.

But for firms in the highly regulated financial sector, the cost of a data breach is even higher -- rising to $239 per compromised record.

"The value of the data a financial firm has is much higher than companies in other sectors. They have personal information such as your account information and your social security number," explains John Dasher of PGP Corporation, which sponsored the survey together with Vontu.

As a result, financial institutions who suffer a data breach tend to offer customers credit protection, and offer to change account numbers --which all add up to the total cost incurred by a company after a breach.

Reputational damage control is particularly high on the agenda for financial firms. Overall, companies in all industries reported a 3% rise this year on public relations and communications expenses following an incident.

"If you're in the financial sector, what's more important than your brand, when you've spent years trying to build trust with your clients?" says Dasher.

Meanwhile, as firms continue to outsource, the Ponemon study revealed that third-party breaches are on the rise.

Breaches by contractors, consultants, outsourcers and business partners, were reported by 40 percent of companies surveyed, up from 29 percent in 2006.

The study also showed that third party breaches are more costly than those incurred by the enterprise itself – averaging $231 per compromised record.