	Financing liabilities ^(b)						Other assets
	Borrowings (including finance leases) excluding			Debt-related derivatives (included in Other financial assets/			Cash/			Other		Net
	overdrafts ^(a)			liabilities)			overdrafts ^(b)			investments ^(c)		(debt)/cash
Year ended 31 December 2018	US$m			US$m			US$m			US$m		US$m
Analysis of changes in consolidated net cash/(debt)
Opening balance		(15,173	)		(177	)		10,547			958		(3,845	)
Foreign exchange adjustment		126			(64	)		151			-		213
Cash movements excluding exchange movements		2,246			51			191			1,557		4,045
Other non-cash movements		50			(98	)		(117	)		7		(158	)
Closing balance		(12,751	)		(288	)		10,772			2,522		255

	Financing liabilities ^(b)						Other assets
	Borrowings (including finance leases) excluding			Debt-related derivatives (included in Other financial assets/			Cash/			Other		Net
	overdrafts ^(a)			liabilities)			overdrafts ^(b)			investments ^(c)		debt
Year ended 31 December 2017	US$m			US$m			US$m			US$m		US$m
Analysis of changes in consolidated net debt
Opening balance		(17,618	)		(408	)		8,189			250		(9,587	)
Foreign exchange adjustment		(303	)		245			(12	)		-		(70	)
Cash movements excluding exchange movements		2,777			7			2,370			705		5,859
Other non-cash movements		(29	)		(21	)		-			3		(47	)
Closing balance		(15,173	)		(177	)		10,547			958		(3,845	)

(a)

Borrowings (including finance leases) at 31 December 2018 differ from total borrowings on the balance sheet as they exclude overdrafts of US$1 million (31 December 2017: US$3 million), other current financial liabilities of US$761 million (31 December 2017: US$352 million) and other non-current financial liabilities US$407 million (31 December 2017: US$524 million).

(b)

Closing cash/overdrafts at 31 December 2018 differ from cash and cash equivalents on the balance sheet as they include overdrafts of US$1 million which have been classified as a financial liability (31 December 2017: US$3 million). Other non-cash movements represents the reclassification of cash and cash equivalents in disposal groups to assets held for sale.

(c)	Other investments comprise US$2,522 million (2017: US$958 million) of highly liquid financial assets held in managed investment funds classified as held for trading.

Further information relating to the currency and interest rate exposures arising from net debt and related derivatives is given in note 30.