When is a correction not a correction?

This correction is not a correction:

Correction: A Rand survey put the previously uninsured rate at about 36 percent of new marketplace enrollees. An earlier version of this story described the percentage as the "insured rate."

This correction is a correction:

Correction: About 60 percent of people living in Crimea identify themselves as Russian. An earlier version of this story described the statistic differently. This post was updated at 1 p.m. March 3, 2014.

And this is how we can tell the difference.

We pointed out the error in the Sununu fact check over a month ago. To its credit, PolitiFact appended a correction to the article after only a little external prodding.  But PolitiFact has never added the Sununu item to its list of corrections or updates.

The takeaway?  Don't view PolitiFact's corrections page as any kind of accurate measure of its mistakes.  PolitiFact doesn't even put all the mistakes it admits on the corrections page, let alone the mistakes it refuses to acknowledge.