Six Percent.

After all the fuss and bother about "Rate Shock!!" in 2015 (aka "Step #8 on the It'll-Destroy-America-To-Might-Suck-Someday chart"), PricewaterhouseCoopers, which has been tracking not just the average 2015 rate requests or approved rates but is also accounting for factors such as...

...metal level/plan design, age, and geography, on health insurance plan premiums. At present, certain states are only reporting partial information about next year’s rates, and others are only reporting percentages that rates will change without sharing actual premium data. Unless otherwise noted, only individual health insurance filings containing rate information have been included in this analysis.

It's also important to note that PwC's rate charts also include off-exchange premiums; in some cases these are identical to the ACA exchange policies, but in other cases they aren't. When you take all of that stuff into account (still not complete; there's still 12 states which they don't have data for, and 32 states only appear to have on-exchange data), you end up with...

...As of September 25, 2014, six states—Colorado, Maryland, New York, Ohio, Oregon, and Rhode Island—as well as the District of Columbia have announced approved rates for both on-exchange and off-exchange health plans on the individual market. In total, HRI has collected premium data from 38 states and the District of Columbia.

Among the six states and DC with final rate announcements, the average premium (across metal tiers and ages) is about $327, and the average premium increase from 2014 is 2.5%. By contrast, the average premium increase across all reporting states is 6.0% and the average premium is $382.

That's right. All the caveats above notwithstanding, it looks very much like the overall average premium rate increase on the individual market for 2015 will only be around 6%.

As Dan Mangan at CNBC put it:

Dire warnings by Obamacare opponents of dramatically higher insurance premium prices in 2015 are not being borne out nationally, according tonew data showing proposed prices are rising moderately, on average, nationally.

As for the on-exchange vs. off-exchange factor, it doesn't look like that was much of one:

PwC's announced averages are based on all individual plans that will be sold either on the Obamacare exchanges or in the open market. The company said it found no significant distinction between those two submarkets.