16. Trade and other receivables


	2017 $m		2016 $m
Current
Trade receivables		452		368
Other receivables		23		25
Prepayments		74		77
Loans to and receivables from associates		2		2

		551		472

Non-current
Loans to associates		—		8

Trade and other receivables are designated as loans and receivables and are held at amortised cost.

Trade receivables are non-interest-bearing and are generally on payment terms of up to 30 days. The fair value of trade and other receivables approximates their carrying value.

The maximum exposure to credit risk for trade and other receivables, excluding prepayments, at the end of the reporting period by geographic region is:


	2017 $m		2016 $m
Americas		305		256
Europe		51		43
AMEA		71		61
Greater China		50		43

		477		403

The ageing of trade and other receivables, excluding prepayments, at the end of the reporting period is:


	2017							2016
	Gross $m		Provision $m			Net $m		Gross $m		Provision $m			Net $m
Not past due		333		(1	)		332		289		(1	)		288
Past due 1 to 30 days		68		(2	)		66		58		(3	)		55
Past due 31 to 180 days		82		(7	)		75		64		(7	)		57
Past due more than 180 days		71		(67	)		4		61		(58	)		3

		554		(77	)		477		472		(69	)		403

The credit risk relating to balances not past due is not deemed to be significant.

The movement in the provision for impairment of trade and other receivables during the year is as follows:


	2017 $m			2016 $m			2015 $m
At 1 January		(69	)		(56	)		(47	)
Provided		(15	)		(25	)		(28	)
Amounts written back		2			5			12
Amounts written off		6			5			7
Exchange adjustments		(1	)		2			—

At 31 December		(77	)		(69	)		(56	)