Many financial stocks have been on a tear since the Federal Reserve's surprise 75-basis point inter-meeting rate cut on January 22. For example, the KBW Bank Index -- which has an equivalent exchange-traded fund, the KBW Bank ETF (AMEX: KBE) -- has rallied 16.1%, beating the S&P 500 index by more than 10 percentage points.

Yet not all financial sub-groups have kept pace with the banks. For instance, after performing well in relative terms during the fourth quarter, insurers have stalled, with the KBW Insurance Index -- which has an equivalent exchange-traded fund, the KBW Insurance ETF (AMEX: KIE) -- more-or-less tracking the move in the overall market in recent weeks.

Banks shares have been buffeted by ill winds in recent months, including the housing and subprime finance meltdowns, and the sector has been among the stock market's worst performing groups.

Insurance shares, meanwhile, have lost some ground relative to the broad market but have outperformed banks and other financial shares by a wide margin.

Arguably, that suggests investors see little real impact on insurers from the problems affecting their counterparts in banking and elsewhere. However, in a financial environment where margins are low and risk is being repriced, in some cases dramatically, I wonder if the bulls on insurance stocks might be missing something?

Whether they offer coverage against calamities such as floods or fire, or protect policyholders from financial loss due to illness or death, insurance companies are in the business of acquiring risk -- albeit for a price.