California: Net attrition rate appears to be 3-4% per month since April (UPDATE: Perhaps not...)

Chad Terhune of the LA Times has a great story about how CoveredCA is ramping up their efforts for the 2nd year of open enrollment. It's a good read overall, but one number in the opening sentence leapt out at me:

Looking to avoid the pitfalls and confusion that surrounded the launch of Obamacare, California is gearing up to get 1.2 million people to renew their health policies for next year.

This caught my eye because the total QHP enrollment number for California was actually 1,405,102 as of 4/19.

Now, Peter Lee did state that 85% of that number had paid their first month's premium as of just a week later, by 4/27...and as it happens, 1.2 / 1.4 = 85.7%, so it's possible that this is what the "1.2 million" refers to.

However, that would only be the case if a) the number of that original 1.4 million who paid up never rose above 85% (which I highly doubt, since a couple hundred thousand of the policies didn't even start coverage for another 4 days), and b) if no one else has enrolled in the off-season in CA, which is even less likely. In fact, my projection suggests that roughly 1,600 people have been enrolling in CoveredCA per day since then, or around 214,000 on top of the original 1.4 million...for around 1.6 million total enrollees.

Assuming around 10% never did pay up, that would leave around 1.46 million who paid for their first month's premium...so if there's 1.2 million people currently fully enrolled & paying up, that's about a 17.8% net attrition rate over 4 1/2 months, or around 4% per month.

On the other hand, if the eventual payment rate in CA has fallen somewhere between 85 & 90%, that would mean about 1.41 million have actually paid, for a total attrition of around 14.9% over 4 1/2 months, or 3.3% per month.

Of course, there's a lot of suppositions here. The irony is that if CA's off-season enrollments are lower than I estimate, their retention rate is actually better (since you'd be dividing 1.2 million into a smaller total). The same holds true with the "How many have PAID???" attack: The worse that percentage is, the better the retention rate after the first month must be, by definition!

Since I'm guessing at some of these numbers, I can't pin down an exact attrition rate, but it looks pretty certain to be somewhere between 3-4%. This is a bit higher than my overall national projection, but as I just noted, the rate is ranging from as low as 0.33% per month up to over 6% so far.

I've asked Mr. Terhune if he can clarify the numbers a bit more, but with CA holding almost 18% of all QHP enrollments nationally, this is a major piece of the puzzle being put together...

UPDATE 09/06/14: Terhune has gotten back to me, sort of:

@charles_gaba always appreciate your analysis. 1.2M is last official paid figure for now and shows up in other state docs

— Chad Terhune (@chadterhune) September 6, 2014

Hmmm...ok, that really doesn't tell me anything about how many more have enrolled since 4/19, but at least it confirms that the 1.2M figure isn't a misstatement on the part of the official he interviewed. Will see if I can find out more...

UPDATE 09/06/14: (sigh) OK, never mind...maybe. It looks like there's a good chance that this 1.2M figure is simply rehashing of the "85% paid" report from back in late April...in which case it doesn't tell me much about updates since then whatsoever:

@charles_gaba sounds right, been repeated some since then. Special enrollment is a wild card

— Chad Terhune (@chadterhune) September 6, 2014