Bunge's short-term borrowings are typically sourced from various banking institutions and the U.S. commercial paper market. Bunge also borrows from time to time in local currencies in various foreign jurisdictions. Interest expense includes facility commitment fees, amortization of deferred financing costs and charges on certain lending transactions, including certain intercompany loans and foreign currency conversions in Brazil. The weighted-average interest rate on short-term borrowings as of December 31, 2011 and 2010 was 4.47% and 2.53%, respectively.

	December 31,

(US$ in millions)	2011		2010
Lines of credit:
Secured	$	—	$	15
Unsecured, variable interest rates from 0.33% to 29.10% ⁽¹⁾		719		1,703

Total short-term debt	$	719	$	1,718

⁽¹⁾: Includes $67 million of local currency borrowings in Eastern Europe at a weighted average interest rate of 27.81% as of December 31, 2011.

In November 2011, Bunge amended the $575 million five year liquidity facility for its commercial paper program, scheduled to mature in June 2012, to extend the expiration date of the liquidity banks' commitments to November 2016. In addition, the total commitment under the liquidity agreement was increased from $575 million to $600 million.

At December 31, 2011, Bunge had $73 million outstanding amounts under its $600 million commercial paper program. The commercial paper program is supported by committed back-up bank credit lines (the liquidity facility) equal to the amount of the commercial paper program provided by lending institutions that are rated at least A-1 by Standard & Poors and P-1 by Moody's Investors Services. The liquidity facility, which matures in November 2016, permits Bunge, at its option, to set up direct borrowings or issue commercial paper in an aggregate amount of up to $600 million. The cost of borrowing under the liquidity facility would typically be higher than the cost of borrowing under our commercial paper program. At December 31, 2011, no borrowings were outstanding under these committed back-up bank credit lines.

In addition to the committed facilities noted above, from time-to-time, Bunge enters into uncommitted short-term credit lines as necessary based on our liquidity requirements. At December 31, 2011, $400 million was outstanding under these uncommitted short-term credit lines. In addition, Bunge's operating companies had $246 million in short-term borrowings outstanding from local bank lines of credit at December 31, 2011 to support working capital requirements.

At December 31, 2011, Bunge had approximately $527 million of unused and available borrowing capacity under its commercial paper program and committed short-term credit facilities.