and Assumptions.

Credit Ratings

Two major corporate debt-rating organizations, Moody’s and S&P, assign ratings to our short-term and long-term debt. A security rating is not a recommendation to buy, sell or hold securities and the rating is subject to revision or withdrawal at any time by the rating organization. Each rating should be evaluated independently of any other rating.

The following table provides the current ratings assigned by these rating agencies to our commercial paper and senior unsecured non-credit- enhanced long-term debt:

               We have available lines of credit and revolving credit agreements with a group of banks and other financial intermediaries. We maintain cash and cash equivalent balances and short-term investments in excess of our commercial paper and other short-term borrowings. As of December 31, 2013, we had access to $8.6 billion of lines of credit, of which $961 million expire within one year. Of these lines of credit, $8.4 billion are unused, of which our lenders have committed to loan us $7.1 billion at our request. Also, $7.0 billion of our unused lines of credit, all of which expire in 2018, may be used to support our commercial paper borrowings.

Global Economic Conditions

The challenging economic environment has not had, nor do we anticipate it will have, a significant impact on our liquidity. Due to our significant operating cash flows, financial assets, access to capital markets and available lines of credit and revolving credit agreements, we continue to believe that we have, and will maintain, the ability to meet our liquidity needs for the foreseeable future. As markets change, we continue to monitor our liquidity position. There can be no assurance that the challenging economic environment or a further economic downturn would not impact our ability to obtain financing in the future.

Contractual Obligations

Payments due under contractual obligations as of December 31, 2013, mature as follows:

The above table includes amounts for potential milestone payments under collaboration, licensing or other arrangements, if the payments are deemed reasonably likely to occur. Payments under these agreements generally become due and payable only upon the achievement of certain development, regulatory and/or commercialization milestones, which may span several years and which may never occur.

In 2014, we expect to spend approximately $1.3 billion on property, plant and equipment. Planned capital spending mostly represents investment to maintain existing facilities and capacity. We rely largely on operating cash flows to fund our capital investment needs. Due to our significant operating cash flows, we believe we have the ability to meet our capital investment needs and anticipate no delays to planned capital expenditures.

Off-Balance Sheet Arrangements

In the ordinary course of business and in connection with the sale of assets and businesses, we often indemnify our counterparties against certain liabilities that may arise in connection with a transaction or that are related to activities prior to a transaction. These indemnifications typically pertain to environmental, tax, employee and/or