Cost	Balance at 1 January 2017		Additions		Disposals			Transfers			Impairment			Effects of movements in exchange rates		Balance at 31 December 2017
Telecommunication licenses		8,039,431		10,154		—			69,945			—			20,098		8,139,628
Computer software		6,076,405		470,457		(8,624	)		569,153			—			9,725		7,117,116
Transmission line software		71,602		218		—			—			—			—		71,820
Central betting system operating right		11,981		—		—			—			—			—		11,981
Indefeasible right of usage		46,017		66,539		—			—			—			—		112,556
Brand name		7,040		—		—			—			—			—		7,040
Customer base		15,512		—		—			—			—			—		15,512
Goodwill		32,834		—		—			—			—			—		32,834
Other		38,321		5,016		—			(588	)		—			—		42,749
Construction in progress		142,875		620,463		—			(638,357	)		—			2,656		127,637

Total		14,482,018		1,172,847		(8,624	)		153			—			32,479		15,678,873

Accumulated amortization
Telecommunication licenses		1,878,895		537,162		—			—			—			3,173		2,419,230
Computer software		4,237,996		537,805		(8,120	)		—			1,219			1,980		4,770,880
Transmission line software		58,203		3,498		—			—			767			—		62,468
Central betting system operating right		10,588		903		—			—			—			—		11,491
Indefeasible right of usage		18,785		4,489		—			—			—			—		23,274
Brand name		5,808		704		—			—			—			—		6,512
Customer base		11,286		488		—			—			—			—		11,774
Other		24,468		8,366		—			—			—			—		32,834

Total		6,246,029		1,093,415		(8,120	)		—			1,986			5,153		7,338,463

Net book amount		8,235,989		79,432		(504	)		153			(1,986	)		27,326		8,340,410

Amortization expenses for the years ended 31 December 2017, 2016 and 2015 amounting to TL 1,095,401, TL 921,812 and TL 549,251, respectively include impairment losses and are recognized in cost of revenue.

Impairment losses on intangible assets for the years ended 31 December 2017, 2016 and 2015 are TL 1,986, TL 3,181 and nil respectively and are recognized in amortization expenses.

Computer software includes capitalized software development costs that meet the definition of an intangible asset. The amount of capitalized development costs is TL 124,504 for the year ended 31 December 2017 (31 December 2016: TL 126,916).

The amortization expenses related to capitalized software development costs for the years ended 31 December 2017, 2016 and 2015 amounting to TL 37,532, TL 30,148 and TL 28,560, respectively are recognized in cost of revenue.


Cost	Balance at 1 January 2016		Additions			Disposals			Transfers			Impairment			Effects of movements in exchange rates		Balance at 31 December 2016

Telecommunication licenses		3,950,729		34,494			(4	)		4,021,090			—			33,122		8,039,431
Computer software		5,342,056		329,836			(6,444	)		390,248			—			20,709		6,076,405
Transmission line software		71,506		96			—			—			—			—		71,602
Central betting system operating right		11,907		—			—			74			—			—		11,981
Indefeasible right of usage		42,132		3,885			—			—			—			—		46,017
Brand name		7,040		—			—			—			—			—		7,040
Customer base		15,512		—			—			—			—			—		15,512
Goodwill		32,834		—			—			—			—			—		32,834
Other		29,713		8,607			(184	)		185			—			—		38,321
4.5G license not yet available for use		3,984,954		33,316			—			(4,018,270	)		—			—		—
Construction in progress		52,597		478,179			—			(391,496	)		—			3,595		142,875

Total		13,540,980		888,413			(6,632	)		1,831			—			57,426		14,482,018

Accumulated amortization
Telecommunication licenses		1,429,944		445,069			(4	)		—			—			3,886		1,878,895
Computer software		3,771,710		454,111			(2,972	)		—			—			15,147		4,237,996
Transmission line software		52,058		3,615			—			—			2,530			—		58,203
Central betting system operating right		9,663		925			—			—			—			—		10,588
Indefeasible right of usage		15,446		3,339			—			—			—			—		18,785
Brand name		5,104		704			—			—			—			—		5,808
Customer base		10,111		1,175			—			—			—			—		11,286
Other		14,307		9,693			(183	)		—			651			—		24,468

Total		5,308,343		918,631			(3,159	)		—			3,181			19,033		6,246,029

Net book amount		8,232,637		(30,218	)		(3,473	)		1,831			(3,181	)		38,393		8,235,989