	September 30,		December 31,
(US$ in millions)	2015		2014
Prepaid commodity purchase contracts (1)	$	355	$	153
Secured advances to suppliers, net (2)	441		520
Unrealized gains on derivative contracts, at fair value	1,676		1,569
Recoverable taxes, net	236		349
Margin deposits	352		323
Marketable securities, at fair value	132		108
Deferred purchase price receivable, at fair value (3)	84		78
Prepaid expenses	173		183
Other	417		522

Total	$	3,866	$	3,805

(1)

Prepaid commodity purchase contracts represent advance payments against fixed price contracts for future delivery of specified quantities of agricultural commodities.

(2)

Bunge provides cash advances to suppliers, primarily Brazilian farmers of soybeans and sugarcane, to finance a portion of the suppliers’ production costs. Bunge does not bear any of the costs or risks associated with the related growing crops. The advances are largely collateralized by future crops and physical assets of the suppliers, carry a local market interest rate and settle when the farmer’s crop is harvested and sold. The secured advances to farmers are reported net of allowances of $1 million and $2 million at September 30, 2015 and December 31, 2014, respectively.

Interest earned on secured advances to suppliers of $7 million and $8 million for the three months ended September 30, 2015 and 2014, respectively, and $27 million and $27 million for the nine months ended September 30, 2015 and 2014, respectively, is included in net sales in the condensed consolidated statements of income.

(3)

Deferred purchase price receivable represents additional credit support for the investment conduits in Bunge’s accounts receivables sales program (see Note 12).