The results of each segment are measured by income before income taxes and equity in net earnings from Kindred at Home, or segment earnings. Transactions between reportable segments primarily consist of sales of services rendered
which are detailed on CMS’ website, we anticipate that the proposals in the Advance Notice would result in a change to our benchmark funding relatively in line with CMS’ estimate.
The consolidated operating cost ratio for 2019 was 11.5%, decreasing 180 basis points from 13.3% in 2018 primarily due to the suspension of the health insurance industry fee in 2019, scale efficiencies associated with growth in our Medicare Advantage membership, and significant operating cost efficiencies in 2019 driven by previously implemented productivity initiatives. These improvements were partially offset by strategic investments in our integrated care delivery model, the impact of higher compensation expense accruals in 2019 for the AIP offered to employees across all levels, increased spending associated with the Medicare AEP, and charges associated with workforce optimization. The higher compensation accruals resulted from our continued strong performance, including customer satisfaction as measured by the net promoter score, along with higher than anticipated individual Medicare Advantage membership growth. The nondeductible health insurance industry fee impacted the operating cost ratio by approximately 180 basis points in 2018.
Individual Medicare Advantage membership increased 523,200 members, or 17.1%, from 3,064,000 members as of December 31, 2018 to 3,587,200 members as of December 31, 2019, primarily due to membership additions associated with the 2019 AEP and Open Election Period, or OEP, for Medicare beneficiaries. The OEP sales period, which ran from January 1 to March 31, added approximately 43,700 members. Since the conclusion of the OEP, enrollment continued to increase due to strong sales to age-ins and those eligible for Dual Eligible Special Need Plans, or D-SNP. Individual Medicare Advantage membership includes 288,200 D-SNP members as of December 31, 2019, a net increase of 69,600, or 31.8%, from 218,600 December 31, 2018. For the full year 2020, we anticipate a net membership increase in our Individual Medicare Advantage offerings of 270,000 members to 330,000 members.
Fully-insured commercial group medical membership decreased 96,100 members, or 9.6% from 1,004,700 members as of December 31, 2018 primarily reflecting lower membership in small group accounts due in part to more small group accounts selecting level-funded ASO products in 2019, as well as the loss of certain large group accounts due to the competitive pricing environment. The portion of group fully-insured commercial medical membership in small group accounts was approximately 59% at December 31, 2019 and 61% at December 31, 2018.
For additional information on our liquidity risk, please refer to Item 1A. - Risk Factors in this 2019 Form 10-K.
The following table provides a historical perspective regarding the accrual and payment of our benefits payable, excluding military services. Components of the total incurred claims for each year include amounts accrued for current year estimated benefits expense as well as adjustments to prior year estimated accruals. Refer to Note 11 to the consolidated financial statements included in Item 8. - Financial Statements and Supplementary Data for Retail and Group and Specialty segment tables including information about incurred and paid claims development as of December 31, 2019, net of reinsurance, as well as cumulative claim frequency and the total of IBNR included within the net incurred claims amounts.
At December 31, 2019, goodwill and other long-lived assets represented 21% of total assets and 50% of total stockholders’ equity, compared to 23% and 58%, respectively, at December 31, 2018.
In February 2016, the FASB issued new guidance related to accounting for leases which requires lessees to record assets and liabilities reflecting the leased assets and lease obligations, respectively, while following the dual model for recognition in statements of income requiring leases to be classified as either operating or finance. Operating leases will result in straight-line expense (similar to current operating leases) while finance leases will result in a front-loaded expense pattern (similar to current capital leases). We adopted the new standard effective January 1, 2019, as allowed, using the modified retrospective approach. We elected the practical expedients of not reassessing whether any expired or existing contracts are or contain leases, not reassessing the lease classification for any expired or existing leases and not reassessing any initial direct costs for existing leases. In addition, we elected the practical expedient to not separate lease and nonlease components for all of our asset classes. We made a permitted accounting policy election to not apply the new guidance to leases with an initial term of 12 months or less. We recognize those lease payments in the condensed consolidated statement of income on a straight-line basis over the lease term. As of January 1, 2019, the adoption of the standard resulted in recognition of lease liabilities of approximately $470 million and right-of-use, or ROU, assets of $436 million, which equals the lease liabilities net of accrued rent and lease incentives. The standard does not materially affect our results of operations, cash flows and liquidity. See Note 10 for further information.
Our debt is recorded at carrying value in our consolidated balance sheets. The carrying value of our senior notes debt outstanding, net of unamortized debt issuance costs, was $5,366 million at December 31, 2019 and $4,774 million at December 31, 2018. The fair value of our senior note debt was $5,916 million at December 31, 2019 and $4,885 million at December 31, 2018. The fair value of our senior note debt is determined based on Level 2 inputs, including quoted market prices for the same or similar debt, or if no quoted market prices are available, on the current prices estimated to be available to us for debt with similar terms and remaining maturities.
Proposed Rule as part of the notice-and-comment rulemaking process. Whether, and to what extent, CMS finalizes the Proposed Rule, and any related regulatory, industry or company reactions, could have a material adverse effect on our results of operations, financial position, or cash flows.
We have audited the accompanying consolidated balance sheets of Humana Inc. and its subsidiaries (the “Company”) as of December 31, 2019 and 2018, and the related consolidated statements of income, of comprehensive income, of stockholders’ equity and of cash flow for each of the three years in the period ended December 31, 2019, including the related notes and financial statement schedules listed in the index appearing under Item 15(a)(2) (collectively referred to as the “consolidated financial statements”). We also have audited the Company's internal control over financial reporting as of December 31, 2019, based on criteria established in Internal Control - Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO).
Addressing the matter involved performing procedures and evaluating audit evidence in connection with forming our overall opinion on the consolidated financial statements. These procedures included testing the effectiveness of controls relating to management’s goodwill impairment assessment, including controls over the significant assumptions used in the valuation of the Provider and Clinical Reporting Units. These procedures also included, among others, testing management's process for developing the fair value estimate of the reporting units; evaluating the appropriateness of the discounted cash flow analysis; testing the completeness and accuracy of underlying data used in the analysis; and evaluating the reasonableness of significant assumptions used by management, including the revenue and terminal growth rates and projected operating income, by considering the past performance of the reporting units and considering whether these assumptions were consistent with evidence obtained in other areas of the audit. Professionals with specialized skill and knowledge were used to assist in the evaluation of the appropriateness of the Company’s discounted cash flow analysis and the reasonableness of the significant assumptions, including the terminal growth rates and the discount rate impacting the reporting units’ future cash flows.