During the fourth quarter of 2016, Hurricane Matthew impacted Florida and Georgia before making landfall in South Carolina and also impacting North Carolina. We write property insurance in all four states and are working diligently to provide claim service to our insureds who were impacted by the storm. We have received over 5,000 claims related to Hurricane Matthew and incurred approximately $30,000,000 of pre-tax catastrophe losses, net of reinsurance recoverable, during the fourth quarter of 2016 from this event.
obscured by current year catastrophe losses, losses from lines in run-off and prior year development. Current year catastrophe losses cause our loss trends to vary significantly between periods as a result of their incidence of occurrence and magnitude, and can have a significant impact on the combined ratio. Prior year development is caused by unexpected loss development on historical reserves. We believe it is useful for investors to evaluate these components separately and in the aggregate when reviewing our performance. The most direct comparable GAAP measure is the combined ratio. The underlying combined ratio should not be considered as a substitute for the combined ratio and does not reflect the overall profitability of our business.
The determination of the amount of other-than-temporary impairment is an inherently subjective process based on periodic evaluations of the factors described above. Such evaluations and assessments are revised as conditions change and new information becomes available. We update our evaluations quarterly and reflect changes in other-than-temporary impairments in results of operations as such evaluations are revised. The use of different methodologies and assumptions in the determination of the amount of other-than-temporary impairments may have a material effect on the amounts presented within the consolidated financial statements
(1) Each region is comprised of the following states: Gulf includes Hawaii, Louisiana and Texas, Northeast includes Massachusetts, New Jersey, New York and Rhode Island, and Southeast includes Georgia, North Carolina and South Carolina.
Premiums receivable represents amounts due from our policyholders for billed premiums and related policy fees. We perform a policy-level evaluation to determine the extent to which the balance of premium receivable exceeds the balance of unearned premium. We then age any resulting exposure based on the last date the policy was billed to the policyholder, and we establish an allowance for credit losses for any amounts outstanding for more than 90 days. When we receive payments on amounts previously charged off, we credit bad debt expense in the period we receive the payment. The balances of our allowance for uncollectible premiums totaled $144,000 and $132,000 at December 31, 2016 and 2015, respectively.
The market multiple valuation approach utilizes market multiples of companies with similar businesses and the projected operating earnings of the reporting unit. The discounted cash flow valuation approach requires judgments about revenues, operating earnings projections, capital market assumptions and discount rates. The key inputs, judgments and assumptions necessary in determining estimated fair value of the reporting units include projected operating earnings, current book value, the level of economic capital required to support the mix of business, long-term growth rates, comparative market multiples, control premium, the account value of in-force business, projections of new and renewal business, as well as margins on such business, the level of interest rates, credit spreads, equity market levels, and the discount rate that we believe is appropriate for the respective reporting unit.
When testing goodwill for impairment, we also considers our market capitalization in relation to the aggregate estimated fair value of our reporting unit. We apply significant judgment when determining the estimated fair value of our reporting unit and when assessing the relationship of market capitalization to the aggregate estimated fair value of our reporting unit.
For our investments in U.S. government securities that do not have prices in active markets, agency securities, state and municipal governments, and corporate bonds, we obtain the fair values from our investment custodians which use a third-party valuation service. The valuation service calculates prices for our investments in the aforementioned security types on a month-end basis by using several matrix-pricing methodologies that incorporate inputs from various sources. The model the valuation service uses to price U.S. government securities and securities of states and municipalities incorporates inputs from active market makers and inter-dealer brokers. To price corporate bonds and agency securities, the valuation service calculates non-call yield spreads on all issuers, uses option-adjusted yield spreads to account for any early redemption features, then adds final spreads to the U.S. Treasury curve at 3 p.m. (ET) as of quarter end. Since the inputs the valuation service uses in their calculations are not quoted prices in active markets, but are observable inputs, they represent Level 2 inputs.
In December 2014, we began funding our investment in the Kayne Anderson Senior Credit Fund II (KSCF). KSCF is a private placement offered by Kayne Anderson Capital Advisors, L.P., an S.E.C. registered investment advisor with approximately $25 billion in assets under management. KSCF will deploy its assets across a variety of loan types with three to five year maturities in senior secured positions to support acquisitions, growth, add-ons, recapitalizations, restructuring and bridge financing. KSCF’s investment strategies include upstream oil and gas companies, energy infrastructure, specialized real estate, middle market credit, growth private equity and distressed municipal opportunities.
Basic earnings per share (EPS) is based on the weighted average number of common shares outstanding for the period, excluding any dilutive common share equivalents. Diluted EPS reflects the potential dilution resulting from vesting of restricted stock awards. The following table shows the computation of basic and diluted EPS for the years ended December 31, 2016, 2015 and 2014:
Amortization expense was $10,910,000, $3,090,000 and $460,000 for the years ended December 31, 2016, 2015 and 2014, respectively. The large increase in amortization expense in 2016 was due to the amortization of intangible assets and VOBA acquired as part of the IIC acquisition. Estimated amortization expense to be recognized by the Company over the next five years is as follows:
For the 2016 contract year, UPC Insurance has elected a 45% participation rate with the FHCF and purchased replacement coverage from private insurers for the remaining 45%. Of the $1,515,197,000 in excess of $10,000,000, we estimate the mandatory FHCF layer will provide approximately $354,015,000 (45% of $786,700,000) of aggregate coverage for losses in excess of $246,002,000. The private market FHCF replacement coverage provides another $346,182,000 of aggregate protection (45% of $769,293,000) in excess of $244,206,000 layer for Florida only on a fully collateralized basis that also inures to the benefit of all other private reinsurance coverage.
Our long-term debt at December 31, 2016 and 2015 included a note payable to the Florida State Board of Administration (SBA Note). During the year ended December 31, 2016, we paid $1,177,000 and $219,000 of principal and interest, respectively. At December 31, 2016 and 2015, we owed $11,176,000 and $12,353,000, respectively, on the note and the interest rate was 1.56% and 2.05%, respectively.
UPC Insurance's reinsurance affiliate, which is based in the Cayman Islands, made an irrevocable election under section 953(d) of the U.S. Internal Revenue Code of 1986, as amended, to be treated as a domestic insurance company for U.S. Federal income tax purposes. As a result of this election, our reinsurance subsidiary is subject to United States income tax on its worldwide income as if it were a U.S. corporation.