b'Other expenses, net. Other expenses, net decreased by $17.8 million during the year endedDecember 31, 2017 primarily a result of a $6.3 million decrease in disputed charges and related costsand a $14.0 million decrease in inventory impairments partially offset by $3.5 million in insurancesettlements related to the riser claim in 2016.Income tax expense (benefit). The Companys effective tax rates for the years ended December 31,2017 and 2016 were 25% and 4%, respectively. The effective tax rates for the periods presented wereimpacted by losses, primarily related to exploration expenses, incurred in jurisdictions in which we arenot subject to taxes and losses incurred in jurisdictions in which we have valuation allowances againstour deferred tax assets and therefore we do not realize any tax benefit on such expenses or losses aswell as the impact of the changes in U.S. income tax law. The effective tax rate in Ghana is impactedby timing of non-deductible expenditures incurred associated with the damage to the turret bearing,due to the expected recovery from insurance proceeds. Any such insurance recoveries would not besubject to income tax. Income tax expense increased by $55.7 million during the year endedDecember 31, 2017, as compared with the year ended December 31, 2016, primarily as a result ofhigher oil revenue in Ghana and mark-to-market gains on our oil derivatives and the impact of changesin U.S. tax law, partially offset by higher depletion and depreciation associated with TEN production.Liquidity and Capital ResourcesWe are actively engaged in an ongoing process of anticipating and meeting our fundingrequirements related to our strategy as a full-cycle E&P company. We have historically met our fundingrequirements through cash flows generated from our operating activities and obtained additionalfunding from issuances of equity and debt, as well as partner carries.While we are presently in a strong financial position, commodity prices remain volatile and couldnegatively impact our ability to generate sufficient operating cash flows to meet our fundingrequirements. To partially mitigate this price volatility, we maintain a hedging program. Our investmentdecisions are based on longer-term commodity prices based on the long-term nature of our projectsand development plans. Also, BP has agreed to partially carry our exploration, appraisal anddevelopment program in Mauritania and Senegal up to a contractually agreed cap. Current commodityprices, combined with our hedging program, partner carries and our current liquidity position supportour dividend and capital program for 2019.As such, our 2019 capital budget is based on our exploitation and production plans for Ghana,Equatorial Guinea and the U.S. Gulf of Mexico, our infrastructure-led exploration program inEquatorial Guinea and the U.S. Gulf of Mexico our appraisal activities in our emerging basins and ourbasin opening exploration across the portfolio.Our future financial condition and liquidity can be impacted by, among other factors, the successof our exploitation, exploration and appraisal drilling programs, the number of commercially viable oiland natural gas discoveries made and the quantities of oil and natural gas discovered, the speed withwhich we can bring such discoveries to production, the reliability of our oil and gas productionfacilities, our ability to continuously export oil and gas, our ability to secure and maintain partners andtheir alignment with respect to capital plans, the actual cost of exploitation, exploration, appraisal anddevelopment of our oil and natural gas assets, and coverage of any claims under our insurance policies.As part of the Facility amendment and restatement process, the lenders approved aredetermination, setting the borrowing base under our Facility at $1.5 billion (effective February 22,2018) which was increased to $1.7 billion (effective January 31, 2019) after the election to exercise$0.2 billion of additional commitments in the fourth quarter of 2018. The borrowing base calculationincludes value related to the Jubilee, TEN, Ceiba and Okume fields.88'