3 Operating costs

Direct costs

In CHF million	1.1.–31.3.2018	1.1.–31.3.2017
Customer premises equipment and merchandise	306	263
Services purchased	112	107
Costs of obtaining a contract	87	65
Costs to fulfill a contract	13	–
Traffic fees of foreign subsidiaries	114	90
International traffic fees	47	53
National traffic fees	25	28
Total direct costs	704	606

Indirect costs

In CHF million	1.1.–31.3.2018	1.1.–31.3.2017
Salary and social security expenses	713	737
Other personnel expense	10	16
Total personnel expense	723	753

Information technology cost	67	69
Maintenance expense	70	60
Rental expense	52	50
Energy costs	28	27
Advertising and selling expenses	40	54
Consultancy expenses and freelance workforce	43	38
Administration expense	27	28
Allowances for receivables	20	20
Miscellaneous operating expenses	156	144
Total other operating expense	503	490

Capitalised self-constructed assets	(83)	(80)
Gain on sale of property, plant and equipment	(1)	(1)
Miscellaneous income	(19)	(10)
Total capitalised self-constructed assets and other income	(103)	(91)

Total indirect costs	1,123	1,152

Capitalised costs of self-constructed assets include personnel costs for the production of technical installations, the construction of network infrastructures and the development of software for internal use.