short-term commercial paper borrowings and long-term debt to provide for our liquidity requirements. We believe that we have the ability to obtain both short-term and long-term debt to meet our financing needs for the foreseeable future. Due to our significant operating cash flows as well as our financial assets, access to capital markets and available lines of credit and revolving credit agreements, we further believe that we have the ability to meet our liquidity needs for the foreseeable future, which include:

• the working capital requirements of our operations, including our research and development activities;

• investments in our business;

• dividend payments and potential increases in the dividend rate;

• share repurchases;

• the cash requirements associated with our cost-reduction/productivity initiatives;

• paying down outstanding debt;

• contributions to our pension and postretirement plans; and

• business-development activities.

With regard to share repurchases, the Company's new $10 billion share-purchase plan became effective on November 30, 2012. (For additional information about the new share-purchase plan, see the “Share-Purchase Plans” section of this Financial Review.)

Our long-term debt is rated investment grade by both Standard & Poor’s (S&P) and Moody’s Investors Service (Moody's). See the “Credit Ratings” section below. As market conditions change, we continue to monitor our liquidity position. We have taken and will continue to take a conservative approach to our financial investments. Both short-term and long-term investments consist primarily of high-quality, highly liquid, well-diversified, available-for-sale debt securities.

Selected Measures of Liquidity and Capital Resources

The following table provides certain relevant measures of our liquidity and capital resources:

For additional information about the sources and uses of our funds, see the “Analysis of the Consolidated Balance Sheets” and “Analysis of the Consolidated Statements of Cash Flows” sections of this Financial Review. Subsequent Events

On January 28, 2013, our then wholly owned subsidiary, Zoetis, issued $3.65 billion aggregate principal amount of senior notes, net of an original issue debt discount of $10 million. The notes have a weighted-average effective interest rate of 3.30%, and mature at various dates as follows: 1.15% Notes due 2016 ($400 million); 1.875% Notes due 2018 ($749 million); 3.25% Notes due 2023 ($1.349 billion); and 4.7% Notes due 2043 ($1.142 billion). On February 6, 2013, Zoetis also entered into a commercial paper program with a capacity of up to $1.0 billion. No amounts are currently outstanding under this program.

Also on January 28, 2013, we transferred to Zoetis substantially all of the assets and liabilities of our Animal Health business in exchange for all of the Class A and Class B common stock of Zoetis, $1.0 billion of the $3.65 billion senior notes and an amount of cash equal to substantially all of the cash proceeds received by Zoetis from the remaining $2.65 billion senior notes issued. The $1.0 billion of senior notes received by Pfizer were exchanged by Pfizer for the retirement of Pfizer