The Health Care Benefits segment offers a full range of insured and self-insured (“ASC”) medical, pharmacy, dental and behavioral health products and services.
The segment results for the three months and years ended December 31, 2023 and 2022 were as follows:
Total revenues increased 16.1% and 15.6% for the three months and year ended December 31, 2023, respectively, compared to the prior year driven by growth across all product lines.
Adjusted operating income decreased 26.0% for the three months ended December 31, 2023 compared to the prior year primarily driven by growth in the individual exchange business, including the related impact of seasonality, and increased utilization in Medicare Advantage. These decreases were partially offset by higher net investment income in the three months ended December 31, 2023 compared to the prior year.
Adjusted operating income decreased 12.0% for the year ended December 31, 2023 compared to the prior year primarily driven by increased utilization in Medicare Advantage when compared with pandemic influenced utilization levels in the prior year, as well as incremental investments in the business, including investments in service capabilities and member experience. These decreases were partially offset by higher net investment income in the year ended December 31, 2023 compared to the prior year.
The MBR increased from 85.8% to 88.5% in the three months ended December 31, 2023 compared to the prior year and increased from 83.8% to 86.2% in the year ended December 31, 2023 compared to the prior year. These increases were primarily driven by increased utilization in Medicare Advantage, including outpatient and supplemental benefits, when compared with pandemic influenced utilization levels in the prior year, as well as Commercial and Medicaid trends returning to normalized levels, consistent with pricing expectations.
Medical membership as of December 31, 2023 of 25.7 million remained relatively consistent compared with September 30, 2023, as declines in the Medicaid product line were largely offset by increases in the Commercial and Medicare product lines.
Medical membership as of December 31, 2023 of 25.7 million increased 1.3 million members compared with December 31, 2022, reflecting increases in the Commercial and Medicare product lines, including an increase of 1.3 million members related to the individual exchange business within the Commercial product line. These increases were partially offset by a decline in the Medicaid product line, primarily attributable to the resumption of Medicaid redeterminations following the expiration of the public health emergency in May 2023.
The segment experienced favorable development of prior-periods’ health care cost estimates in its Government Services and Commercial businesses during the three months ended December 31, 2023, primarily attributable to 2023 performance.
Prior years’ health care costs payable estimates developed favorably by $675 million during the year ended December 31, 2023. This development is reported on a basis consistent with the prior years’ development reported in the health care costs payable table in the Company’s annual audited financial statements and does not directly correspond to an increase in 2023 operating results.