1, 2019, (ii)a pricing level on our senior unsecured long-term debt ratings at or below Ba2/BB, with an interest rate margin for LIBOR loans of 2.00% and for base rate loans of 1.00% and (iii) maximum principal amount of priority debt up to 7.5% of the consolidated tangible assets and a maximum amount of receivables that can be securitized of $100 million. Subject to certain conditions, including lender approval, we have the right to increase the amount of the Term Loan Facility or the Revolving Credit Facility by an aggregate amount not to exceed $400.0 million. A discussion of our debt and related covenants is included in Note 11 to our consolidated financial statements included in Item 8 of this Annual Report. We were in compliance with all covenants as of December 31, 2018. Certain financing arrangements contain provisions that may result in an event of default if there was a failure under other financing arrangements to meet payment terms or to observe other covenants that could result in an acceleration of payment due. Such provisions are referred to as "cross default" provisions. The Senior Credit Facility and the Senior Notes as described in Note 11 to our consolidated financial statements included in Item 8 of this Annual Report are cross-defaulted to each other. The rating agencies assign credit ratings to certain of our debt. Our access to capital markets and costs of debt could be directly affected by our credit ratings. Any adverse action with respect to our credit ratings could generally cause borrowing costs to increase and the potential pool of investors and funding sources to decrease. In particular, a decline in credit ratings would increase the cost of borrowing under our Senior Credit Facility. Our cash balance decreased by $83.8 million to $619.7 million as of December 31, 2018 as compared with December 31, 2017. The cash decrease included $84.0 million in capital expenditures, $99.4 million in dividend payments and $60.0 million in payments on long-term debt, partially offset by $190.8 million in operating cash inflows. Approximately 57% of our currently outstanding Term Loan Facility and $13.5 million of other short-term borrowings are due to mature in 2019 and 2020. Our Senior Credit Facility matures in October 2020. Our borrowing capacity is subject to financial covenant limitations based on the terms of our Senior Credit Facility and is also reduced by outstanding letters of credit. As of December 31, 2018, we had an available capacity of $513.7 million, no borrowings outstanding and $92.9 million of letters of credit outstanding under our Revolving Credit Facility. Our Revolving Credit Facility is committed and held by a diversified group of financial institutions. For additional information on our Senior Credit Facility, see Note 11 to our consolidated financial statements included in Item 8 of this Annual Report. At December 31, 2018 and 2017, as a result of the values of the plan’s assets and our contributions to the plan, our U.S. pension plan was fully-funded as defined by applicable law. After consideration of our intent to maintain fully funded status, we contributed $20.0 million to our U.S. pension plan in 2018, excluding direct benefits paid of $3.3 million. We continue to maintain an asset allocation consistent with our strategy to maximize total return, while reducing portfolio risks through asset class diversification. Our future results of operations and other forward-looking statements contained in this Annual Report, including this MD&A, involve a number of risks and uncertainties — in particular, the statements regarding our goals and strategies, new product introductions, plans to cultivate new businesses, future economic conditions, revenue, pricing, gross profit margin and costs, capital spending, expected cost savings from our transformation and realignment programs, global economic and political risk, depreciation and amortization, research and development expenses, potential impairment of assets, tax rate and pending tax and legal proceedings. Our future results of operations may also be affected by employee incentive compensation including our annual program and the amount, type and valuation of share-based awards granted, as well as the amount of awards forfeited due to employee turnover. In addition to the various important factors discussed above, a number of other factors could cause actual results to differ materially from our expectations. See the risks described in "Item 1A. Risk Factors" as well as the section titled “Forward- Looking Information is Subject to Risk and Uncertainty” of this Annual Report. Our bookings were $4,019.8 million during 2018. Because a booking represents a contract that can be, in certain circumstances, modified or canceled, and can include varying lengths between the time of booking and the time of revenue recognition, there is no guarantee that bookings will result in comparable revenues or otherwise be indicative of future results. The outlook for the oil and gas industry is heavily dependent on the demand growth from both mature markets and developing geographies. In the short-term, we believe that stable oil prices will support oil and gas upstream and mid-stream investment and we further expect increased investment in later cycle downstream projects due to emerging market growth and certain regulatory requirements, such as IMO 2020. A recovery in the overall level of spending by oil and gas companies could continue to increase demand for our aftermarket products and services. We believe the medium and long-term OUTLOOK FOR 2019 Liquidity Analysis 44