	Land		Buildings			Building improvement			Machinery and equipment			Motor vehicle and other asset			Office equipment			Construction in progress			Total
	US$’000		US$’000			US$’000			US$’000			US$’000			US$’000			US$’000			US$’000
Cost
At January 1, 2019		6,206		47,890			5,715			96,718			5,780			6,722			1,673			170,704
Effects on initial application of IFRS 16	—		—			—			—				(192	)	—			—				(192	)
Adjusted balance at January 1, 2019		6,206		47,890			5,715			96,718			5,588			6,722			1,673			170,512
Additions		—		7			119			292			433			315			2,240			3,406
Disposals		—		—			(4	)		(2,308	)		(524	)		(331	)		—			(3,167	)
Transfer		—		(167	)		746			1,748			180			139			(2,582	)		64
Exchange differences		632		2,813			454			7,419			332			247			47			11,944
At December 31, 2019		6,838		50,543			7,030			103,869			6,009			7,092			1,378			182,759
Additions	—			—			138			239			265			363			15,691			16,696
Disposals	—			—			(31	)		(6,129	)		(483	)		(205	)	—				(6,848	)
Transfer	—			680			152			1,157			115			17			(2,093	)		28
Exchange differences		34		893			47			1,129			63			321			685			3,172
At December 31, 2020		6,872		52,116			7,336			100,265			5,969			7,588			15,661			195,807

Depreciation/Impairment
At January 1, 2019		—		(33,730	)		(3,567	)		(82,948	)		(3,482	)		(5,559	)		—			(129,286	)
Effects on initial application of IFRS 16		—		—			—			—			126			—			—			126
Adjusted balance at January 1, 2019		—		(33,730	)		(3,567	)		(82,948	)		(3,356	)		(5,559	)		—			(129,160	)
Depreciation charge for the year		—		(1,044	)		(338	)		(2,391	)		(541	)		(420	)		—			(4,734	)
Impairment		—		—			(1	)		(550	)		7			(2	)		—			(546	)
Disposals		—		—			4			2,274			477			329			—			3,084
Transfer		—		265			(265	)		—			(64	)		—			—			(64	)
Exchange differences		—		(2,361	)		(297	)		(6,517	)		(185	)		(232	)		—			(9,592	)
At December 31, 2019		—		(36,870	)		(4,464	)		(90,132	)		(3,662	)		(5,884	)		—			(141,012	)
Depreciation charge for the year	—			(962	)		(384	)		(2,301	)		(514	)		(414	)		—			(4,575	)
Impairment	—		—			—				(198	)	—				(4	)		—			(202	)
Disposals	—			—			21			6,128			438			203			—			6,790
Transfer		—		—			—			—			(56	)		—			—			(56	)
Exchange differences	—			(653	)		(29	)		(1,041	)		(63	)		(266	)		—			(2,052	)
At December 31, 2020		—		(38,485	)		(4,856	)		(87,544	)		(3,857	)		(6,365	)		—			(141,107	)

Net book value
At December 31, 2020		6,872		13,631			2,480			12,721			2,112			1,223			15,661			54,700
At December 31, 2019		6,838		13,673			2,566			13,737			2,347			1,208			1,378			41,747
At January 1, 2019		6,206		14,160			2,148			13,770			2,298			1,163			1,673			41,418

In 2020, 2019 and 2018 the Company recorded an impairment loss of $202, $546 and $11 on property, plant and equipment at Sigma Cable, Shanghai Yayang and SFO facilities. The impairment is presented within cost of sales in consolidated income statements, other operating expenses in Note 7(b), and the impairment of property, plant and equipment of ROW, North Asia and Thailand segments in Note 5.

The Company identified impairment at Sigma Cable due to lack of profitability. The Company determined that certain machinery and equipment would not generate the expected future cash flows. The impairment test revealed that the total carrying amount of these assets was greater than their total recoverable amount. After considering the relevant objective evidence, the Company recorded an impairment loss.

The Company performed a valuation for utilized machinery measured at fair value less costs to sell using a cost approach due to closure of the manufacturing facilities at Shanghai Yayang. Its fair value measurement was classified as Level 3 of the fair value hierarchy. After considering the relevant evidence, the key assumption used included replacement costs, residual value and remaining useful life of these existing assets. The impairment test revealed that the recoverable amount was lower than the carrying amount.

The Company considers the market demand for SFO’s products and performed an impairment test on the CGU composed of property, plant and equipment used in the manufacturing of fiber optic cables at SFO. The Company determined the recoverable amount of the CGU to be $0 based on the value in use. The key assumptions used in calculating the value in use included the revenue growth and a discount rate of 14.8%.

The carrying value of motor vehicles under lease arrangements as of December 31, 2020, 2019 and 2018 were $0, $0 and $66, respectively. These assets under lease arrangements are pledged for lease liabilities (Note 25(b)).

Information about the property, plant and equipment that were pledged to others as collaterals is provided in Note 27(e) (i).