Liquidity
Cash and Liquidity. As of December 31, 2019, our principal sources of liquidity included cash, cash equivalents, and short-term investments of $182.7 million, compared to $162.9 million as of December 31, 2018. We generally invest our excess cash balances in low-risk, short-term investments to limit our exposure to market and credit risks.
During the first quarter of 2018, we refinanced our 2015 Credit Agreement which extended the term of the loan to March 2023 as well as obtained a reduction in the interest rate and other fees. The 2018 Credit Agreement increased our liquidity and capital resources position by approximately $30 million.
As part of our 2018 Credit Agreement, we have a $200 million senior secured revolving loan facility with a syndicate of financial institutions that expires in March 2023. As of December 31, 2019, there were no borrowings outstanding on the 2018 Revolver. The 2018 Credit Agreement contains customary affirmative covenants and financial covenants. As of December 31, 2019, and the date of this filing, we believe that we are in compliance with the provisions of the 2018 Credit Agreement.
Our cash, cash equivalents, and short-term investment balances as of the end of the indicated periods were located in the following geographical regions (in thousands):
We generally have ready access to substantially all of our cash, cash equivalents, and short-term investment balances, but may face limitations on moving cash out of certain foreign jurisdictions due to currency controls and potential negative economic consequences. As of December 31, 2019, we had $2.7 million of cash restricted as to use to collateralize outstanding letters of credit.
Cash Flows From Operating Activities. We calculate our cash flows from operating activities beginning with net income, adding back the impact of non-cash items or nonoperating activity (e.g., depreciation, amortization, amortization of OID, impairments, gain/loss from debt extinguishments, deferred income taxes, stock-based compensation, etc.), and then factoring in the impact of changes in operating assets and liabilities.
Our primary source of cash is from our operating activities. Our current business model consists of a significant amount of recurring revenue sources related to our long-term cloud-based and managed services arrangements (mostly billed monthly), payment process transaction services (mostly billed monthly), and software maintenance agreements (billed monthly, quarterly, or annually). This recurring revenue base provides us with a reliable and predictable source of cash. In addition, software license fees and professional services revenues are sources of cash, but the payment streams for these items are less predictable.
The primary use of our cash is to fund our operating activities. Over half of our total operating costs relate to labor costs (both employees and contracted labor) for the following: (i) compensation; (ii) related fringe benefits; and (iii) reimbursements for travel and entertainment expenses. The other primary cash requirements for our operating expenses consist of: (i) computing capacity and related services and communication lines for our outsourced cloud-based business; (ii) paper, envelopes, and related supplies for our statement processing solutions; (iii) transaction fees paid in conjunction with the delivery of services under our payment services contracts; (iv) hardware and software; and (v) rent and related facility costs. These items are purchased under a variety of both short-term and long-term contractual commitments. A summary of our material contractual obligations is provided below.
Table:
 | December 31, | December 31,
 | 2019 | 2018
Americas (principally the U.S.) | $125,309 | $110,385
Europe, Middle East and Africa | 50,477 | 45,884
Asia Pacific | 6,871 | 6,611
Total cash, cash equivalents and short-term investments | $182,657 | $162,880


Question: What did the company do as part of its 2018 Credit Agreement?
Answer: refinanced our 2015 Credit Agreement which extended the term of the loan to March 2023 as well as obtained a reduction in the interest rate and other fees