Health Insurance Marketplace: December Enrollment Report. Methodological Overview


The data reported here have been generated by the information systems of the Centers for Medicare & Medicaid Services (CMS), based on information reported to CMS by SBMs, and information collected by the FFM for states with HHS-supported or fully run Marketplaces (including those run in partnership with states). Data for certain metrics are not yet available for some SBM states due to information system issues. (Please refer to Appendix B for additional methodological information.)

As discussed earlier, this report includes cumulative data for the two month period (10-1-13 to 11-30-13) because some people apply, shop, and select a plan across monthly reporting periods. These counts seek to avoid potential duplication associated with monthly reporting. For example, if a person submitted an application in October, and then selected a Marketplace plan in November, this person would only be counted once in the cumulative data.

We believe that the information contained in this issue brief provides the most systematic “snapshot” of enrollment-related activity in the Marketplaces to date because the data for the various metrics are counted using comparable definitions for data elements across states, and between the SBMs and FFM. It is important to note that the SBM enrollment-related data that are reported in this issue brief represent state data that have been reported to CMS, and may differ from comparable data that have previously been publicly reported on SBM websites or in media reports because that data may be based on different time periods or metric definitions from those used in this report.

View full report


"ib_2013dec_enrollment.pdf" (pdf, 217.64Kb)

Note: Documents in PDF format require the Adobe Acrobat Reader®. If you experience problems with PDF documents, please download the latest version of the Reader®