With 100 days to go before the Obamacare insurance exchange rollout on Oct. 1, let's take a look at the state of these state-based exchanges. This is a key part of the legislation, as it will create competition between insurers and use the free market to drive costs down.

In this video, health-care analyst David Williamson discusses where progress stands on the exchange buildout, along with why most major insurers are cautiously approaching the concept instead of jumping fully onboard.

Follow David on Twitter: @MotleyDavid.

David Williamson has no position in any stocks mentioned. Follow David on Twitter: @MotleyDavid.

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