While it's unfortunate that neither 2014 nor 2015 were included, I have partial data for the first two years of the ACA exchanges from a similar post I put together back in 2019.
It's important to understand the difference between someone selecting a Qualified Health Plan (QHP) from one of the ACA exchanges during the Open Enrollment Period and someone actually being enrolled in an effectuated policy...that is, just because you sign your family up for a policy on HealthCare.Gov or a state-based exchange, you aren't considered effectuated until you actually pay your first monthly premium.
While nearly 21.5 million Americans selected Qualified Health Plans (QHPs) via the federal and state ACA exchanges/marketplaces during the official 2024 Open Enrollment Period (along with an additional 1.3 million signing up for a Basic Health Plan (BHP) program in New York & Minnesota, which CMS continues to inexplicably treat as an afterthought in such reports), not all of them actually pay their first monthly premium (for January) for various reasons:
While nearly 16.4 million Americans selected Qualified Health Plans (QHPs) via the federal and state ACA exchanges/marketplaces during the official 2023 Open Enrollment Period (along with an additional 1.2 million signing up for a Basic Health Plan (BHP) program in New York & Minnesota, which CMS continues to inexplicably treat as an afterthought in such reports), not all of them actually pay their first monthly premium (for January) for various reasons:
Normally I receive notices about these types of data reports directly from CMS via their mailing list, but this time around it wasn't emailed and in fact isn't even posted on the CMS newsroom archive (at least not yet). Fortunately, my eagle-eyed colleague Andrew Sprung grabbed the link from a Health Affairs article and wrote up his own analysis of it.
July 23, 2020 - Early 2020 Effectuated Enrollment Snapshot
This report provides effectuated enrollment, premium, and advance payments of the premium tax credit (APTC) data for the Federally-facilitated and State-based Exchanges (“the Exchanges”) for February 2020 and for the 2019 plan year.
February 2020 Effectuated Enrollment Snapshot Key Findings