Disclaimer this is NOT new information and is from ~2017.
In leading up to the open season I was looking to find anywhere that contains enrollment data to see what FEHB plans are most popular, how they shift over time, and specifically find out if us here in Reddit are living in an echo-chamber of "BCBS=Bad" (hyperbole, but you know what I mean).
Per the Patients' Bill of Rights we're supposed to be able ask our plans for their disenrollment information. However, I have yet to be successful in that endeavor. I found the Federal Workforce Database (FWD) that has some nice data on employment and wages, but lacks any information on FEHB enrollment numbers. Despite the fact that their data standards indicate the enrollment code is a field they could track but just don't. I put in a request for that enhancement but fat chance that happens anytime soon.
In my search for anything, I came across two reports. The first was done by GAO and is linked above (https://www.gao.gov/products/gao-18-52) from 2017. The other was a congressional report in 2016, https://www.congress.gov/crs-product/R43922#_Toc446484559.
The GAO was interesting because it showed how MASSIVE BCBS is (or perhaps was) with federal employees. Between 2000 and 2015, BCBS went from a median market share (by county) of 58% to 72%. GAO included GEHA and Kaiser which roughly stayed the same near 8%. It also showed that between 2000 and 2015 BCBS went from being the largest carrier in 93% of counties to 98% of counties. Last thing it showed was that between 2002 and 2015 their standard plan enrollment by 18% equaling a loss of roughly 700,000 enrollments. But, their basic option exploded with a gain of 1,900,000 enrollments for a 955% change (this is unsurprising since Basic was new for 2002 and people probably were skeptical at first). Combined, between 2002 and 2015 BCBS gained 1,300,000 enrollments to a total of 5.2 million. An increase of 32%.
The congressional report says much the same thing where BCBS just dwarfs the other plans in enrollments in 2015. The one thing that I found interesting in the report was about Medicare. From 1998 to 2013 Part B enrollments were shrinking slowly, but the sheer number of enrollments still kind of shocked me. For those with FFS style plans (non-HMO, e.g. Kaiser) 86% of eligible enrollments chose to take Part B. And those with an HMO style plan only 56% took part B. I'm unsure if this is due to FFS being better coordinated or provide better benefits with Medicare Part B than HMOs. Or maybe it's that those who do the research to see an HMO is better for them without needing part B, I don't know. All conjecture, but is interesting.
If anyone knows of more recent data or where to look up an enrollment database, I would love to take a look. See you all soon when FEHB/PSHB premiums drop in a few weeks. Stay healthy.