We painstakingly analyzed the financial impact a data breach has on a company by examining 43 different companies from a cross section of industries, all of which experienced a significant data breach affecting a range of data records representative of the norm. And knowing that a data breach may cost your company $6.65 million dollars may be all the information that is needed for a company to assign an appropriate budget to those tasked with information security.

In 2008 the average total cost of a data breach was $6.65 million, up from $6.35 million last year and $4.54 in 2005. In 2008, the per-victim cost of a data breach was $202, up from $197 in 2007, and from $138 when the study was launched in 2005. Breaches involving a third party to which data had been outsourced bore a per-victim cost of $231, whereas self contained breaches bore a per-victim cost of $179. Breaches that were the result of a malicious act bore a per-victim cost of $225, whereas breaches that were the result of negligence bore a per-victim cost of $199. Breaches that were the result of a lost of stolen laptop computer bore a per-victim cost of $249, whereas breaches that did not involve a lost or stolen laptop computer bore a per-victim cost of $177. If the data breach was a first-time event for the company the per victim cost was $243, but if the company had experienced a breach previously the per victim cost was $192.

The simple conclusion to these numbers is clear: the financial impact for a company that experiences a data breach is significant and rising. That finding alone may be alarming, but it seems to merely quantify what most people already knew to be true. The "wow" factor comes when you realize that we haven't simply identified the cost of an inevitable outcome, as if to tell the world, "buckle up and brace for impact," but we've shown that companies well have the means to significantly diminish their loss if and when a breach occurs.

Consider the last data point on our list. First-time data breaches cost companies $51 more per victim than for companies who had already learned the hard lessons of data breach. That means the previous experience resulted in a smarter, more efficient response the second time around. Last year the Ponemon Institute began working with risk management firm WillisHRH on a data breach response tracking system called the Privacy Breach Index. We use the PBI to analyze the methods and strategies used by companies when responding to a breach, and the outcome of the response, to create best practices so other organizations don't have to learn from their own experience.