The CTA estimates at least $325M in damages and extortions from Ransomeware which encrypts user files on an infected system and holds users hostage unless they wire money to a special Bitcoin account. An article plus the full PDF report can be found below:

http://www.eweek.com/security/ransomware-operation-racked-up-325m-in-damages-security-firms-say.html

http://cyberthreatalliance.org/cryptowall-report.pdf

The latest version of the CryptoWall ransomware program has raked in more than $325 million for the group behind the criminal operation, researchers from Cyber Threat Alliance stated in a report released on Oct. 29.  The Cyber Threat Alliance (CTA), a group of security companies that have pledged to share threat data with each other, combined a variety of information from its members to identify more than 4,000 malware samples, 800 command-and-control sites and 400,000 attempted infections. The 90-day research effort identified 49 different CryptoWall campaigns that likely caused at least $325 million in damages, according to the companies.