5.General economic, industry sector or individual debt issuers’ financial conditions (including developments and volatility arising from the COVID-19 pandemic, particularly in certain industries that may comprise part of our investment portfolio) that may affect the current market value of securities we own, or that may impair an issuer’s ability to make principal and/or interest payments due on those securities;
Insurance Product Line Segments. The insurance product line segments involve the marketing, underwriting, and administration of policies. Each product line is further segmented by the various distribution channels that market the insurance policies. Each distribution channel operates in a niche market offering insurance products designed for that particular market. Whether analyzing profitability of a segment as a whole, or the individual distribution channels within the segment, the measure of profitability used by management is the underwriting margin, as seen below:
The American Income Life Division markets to members of labor unions and continues to diversify its lead sources by building relationships with other affinity groups, utilizing third-party internet vendor leads and obtaining referrals to facilitate sustainable growth. This division is Globe Life's largest contributor to life premium of any distribution channel at 47% of the Company's 2020 total. Net sales increased 7% to $253 million in 2020 over the 2019 total of $238 million. The underwriting margin, as a percent of premium, was 32% for the twelve months ended December 31, 2020, down from 34% from the prior year primarily due to $18 million of estimated incurred claims related to COVID-19 as well as elevated claims for other causes. Sales growth in our exclusive agencies is generally dependent on growth in the size of the agency force.
deterioration in credit quality of the issuer in effort to maximize risk adjusted capital adjusted returns. We do not engage in trading investments for profit. Therefore, gains or losses which occur in protecting the portfolio or its yield, or which result from events that are beyond our control, are only secondary to our core insurance operations of providing insurance coverage to policyholders. In a bond exchange offer, bondholders may consent to exchange their existing bonds for another class of debt securities. The exchanges on our bonds have generally been the result of mergers and acquisitions, and are offered to move debt to the new or surviving entity. The Company also has alternative investments held under the fair value option with changes recognized in Realized gains (losses) in the Consolidated Statements of Operations.
(2)Globe Life calculates the average life and duration of the fixed maturity portfolio two ways:
When valuations have been obtained for all securities in the portfolio, management reviews and analyzes the prices to ensure their reasonableness, taking into account available and observable information. When two or more valuations are available for a security and the variance between the prices is 10% or less, the close correlation suggests similar observable inputs were used in deriving the price, and the mean of the prices is used. Securities valued in this manner are classified as Level 2. When the variance between two or more valuations for a security exceeds 10%, additional analysis is performed to determine the most appropriate value for that security, using resources such as broker quotes, prices on comparable securities, recent trades, and any other observable market data. Further review is performed on the available valuations to determine if they can be corroborated within reasonable tolerance to any other observable evidence. If one of the valuations or the mean of the available valuations for a security can be corroborated with other observable evidence, then the corroborated value is used and reported as Level 2. The Company uses information and analytical techniques deemed appropriate for determining the point within the range of reasonable fair value estimates that is most representative of fair value under current market conditions. Valuations that cannot be corroborated within a reasonable tolerance are classified as Level 3.
Goodwill: The excess cost of a business acquired over the fair value of net assets acquired is reported as goodwill. In accordance with the guidance, goodwill is subject to impairment testing on an annual basis, or whenever potential impairment triggers occur. Impairment testing involves the performance of a qualitative analysis, which involves assessing current events and circumstances to determine if it is more likely than not that the fair value of a reporting unit is less than its carrying amount. In the event the fair value is less than the carrying value, further testing is required to determine the amount of impairment, if any. If there is an impairment in the goodwill of any reporting unit, it is written down and charged to earnings in the period of the test. Globe Life tested its goodwill annually as of June 30th for each of the years 2018 through 2020. The Company's goodwill was not impaired in any of those periods.
(1)Acquisitions of Level 3 investments in each of the years 2018 through 2020 are comprised of private-placement fixed maturities.
As of December 31, 2020, the Company had one commercial mortgage loan in non-accrual status. As of December 31, 2019, the Company did not have any commercial mortgage loans in non-accrual status.
to reduce the current amount outstanding to $135 million from $150 million outstanding. As of December 31, 2020, the letters of credit outstanding were $135 million.
Litigation: Globe Life Inc. (formerly Torchmark Corporation) and its subsidiaries, in common with the insurance industry in general, are subject to litigation, including putative class action litigation, alleged breaches of contract, torts, including bad faith and fraud claims based on alleged wrongful or fraudulent acts of agents of the Parent Company's insurance subsidiaries, employment discrimination, and miscellaneous other causes of action. Based upon information presently available, and in light of legal and other factual defenses available to the Parent Company and its subsidiaries, management does not believe that it is reasonably possible that such litigation will have a material adverse effect on Globe Life's financial condition, future operating results or liquidity; however, assessing the eventual outcome of litigation necessarily involves forward-looking speculation as to judgments to be made by judges, juries and appellate courts in the future. This bespeaks caution, particularly in states with reputations for high punitive damage verdicts. Globe Life's management recognizes that large punitive damage awards bearing little or no relation to actual damages continue to be awarded by juries in jurisdictions in which the Company has substantial business, creating the potential for unpredictable material adverse judgments in any given punitive damage suit.
Globe Life's tax liability is adjusted to include a provision for uncertain tax positions taken or expected to be taken in a tax return. However, during the years 2018 through 2020, Globe Life did not have any uncertain tax positions which resulted in unrecognized tax benefits.
On September 3, 2020, Globe Life completed the issuance and sale of $50 million in aggregate principal of Globe Life's 2.15% unsecured Senior Notes also due August 15, 2030. These Senior Notes were issued as additional notes under a Second Supplemental Indenture governing the 2.15% Senior Notes issued on August 21, 2020. The Senior Notes are fully fungible and have the same terms as the first issuance. The net proceeds from the sale of the Senior Notes were $49.3 million, after giving effect to the underwriting expenses.