The Insurance Information Institute (III) publishes an online Financial Services Factbook which provides a wealth of statistics about insurance, banking, and securities.  Of particular interest to member of this community is the section on IT Spending which, while short, is helpful for distinguishing the level of IT spending not just among financial institutions, but by type of insurer.  If you're wanting more current, though less comprehensive data, here's an article published earlier this year in Insurance & Technology based on research from TowerGroup that describes how spending is dampened in some areas because of the well-known credit pressures on financial services companies.

Typical IT spend (as a percentage of revenues) for agencies and carriers from Smallwood Maike. 

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