We lease under a non-cancelable operating lease expiring in 2019 approximately 187,000 square feet in an office building in Houston, Texas, which is used for our corporate offices and for offices of several of our subsidiaries. In addition, we lease offices at approximately 570 additional locations for title office operations, production, administrative and technology centers. These additional locations include significant leased facilities in Houston, Texas; Glendale, California; Dallas, Texas; New York, New York; Wilmington, Delaware; Tampa, Florida; St. Louis, Missouri; San Diego, California; and Toronto, Canada.
Operating revenues generated by our ancillary services and corporate segment declined to $19.1 million in the fourth quarter 2016 from $25.2 million in the fourth quarter 2015, primarily due to our exit of the delinquent loan servicing operations completed in the first quarter 2016. Sequentially, operating revenues decreased from $22.2 million in the third quarter 2016, primarily due to revenue declines in our search and valuation services operations. The segment reported a pretax loss of $15.1 million in the fourth quarter 2016 as compared with pretax losses of $19.9 million and $11.5 million in the fourth quarter 2015 and third quarter 2016, respectively.
Provisions for known claims relate primarily to prior policy years as claims are not typically reported until several years after policies are issued. Provisions - Incurred But Not Reported (IBNR) are estimates of claims expected to be incurred over the next 20 years and are subject to considerable judgment in their determination; therefore, it is not unusual or unexpected to experience adjustments to the provisions for both current and prior policy years as additional loss experience on policy years is obtained subsequent to the year of issuance. This loss experience may result in changes to our estimate of total ultimate losses expected (i.e., the IBNR policy loss reserve). Current year provisions - IBNR are recorded on policies issued in the current year as a percentage of premiums realized (provisioning rate). As claims become known, provisions are reclassified from IBNR to known claims. Adjustments relating to large claims (those individually in excess of $1.0 million) may impact provisions either for known claims or for IBNR.
We consider our actual claims payments and incurred loss experience, including consideration of the frequency and severity of claims compared to our actuarial estimates of claims payments and incurred losses in determining whether our overall loss experience has improved or worsened compared to prior periods. We also consider the impact of economic or market factors on particular policy years to determine whether the results of those policy years are indicative of future expectations. In addition, we evaluate the frequency and severity of large losses in determining whether our experience has improved or worsened. Our method for recording the reserves for title losses on both an interim and annual basis begins with the calculation of our current loss provision rate which is applied to our current premium revenues, resulting in a title loss expense for the period. This loss provision rate is set to provide for losses on current year policies and is determined using moving average ratios of recent actual policy loss payment experience (net of recoveries) to premium revenues.
We also evaluate the carrying values of title plants, other intangible assets and other long-lived assets when events occur that may indicate impairment. The process of determining impairment for such assets involves determining whether the carrying amount of the asset is recoverable using the undiscounted cash flows expected from the use and eventual disposition of the asset. If the carrying amount is determined not to be recoverable, we estimate the fair value of the asset using projections of future cash flows, operating results, discount rates and overall market conditions. Any excess of the carrying amount over the fair value is considered as an impairment of the asset. Uncertainties exist in these projections and they are subject to changes relating to factors such as interest rates and overall real estate and financial market conditions, our market capitalization and overall stock market performance. Actual market conditions and operating results may vary materially from our projections. In 2015 and 2014, as a result of our impairment analysis on our other intangible assets, we recorded impairment charges of $1.8 million and $1.7 million, respectively. No impairment loss was recognized during 2016.
Employee costs. Employee costs for the combined business segments decreased $53.9 million, or 8.2%, in 2016 compared to 2015 as a result of the cost management program we completed at the end of 2015, as well as reductions in employee counts tied to volume declines. Employee costs increased $33.9 million, or 5.4%, in 2015 compared to 2014 due to higher revenues in 2015 and the effect of acquisitions made mid-2014 in the ancillary services operations. As a percentage of total operating revenues, employee costs were 30.4%, 32.6% and 33.8% in 2016, 2015 and 2014, respectively. Our total employee count at December 31, 2016, 2015 and 2014 was approximately 6,350, 6,940 and 7,410, respectively.
In 2015, net unrealized investment losses of $5.4 million, which increased our other comprehensive loss, were primarily related to temporary decreases in fair values of corporate and government bond investments and equity securities, partially offset by the increase in fair values of municipal bond investments. Changes in foreign currency exchange rates, primarily related to our Canadian operations, increased other comprehensive loss by $11.1 million, net of taxes, in 2015.