Trade Accounts Receivable Trade accounts receivable less impairment losses amounted to €8,582 million (2016: €10,969 million) on the closing date and were comprised as follows: (XLS:) Download Trade Accounts Receivable 2016 2017 € million € million Trade accounts receivable (before impairments) 11,377 9,007 Accumulated impairment losses (408) (425) Carrying amount, December 31 10,969 8,582 of which noncurrent 144 97 The deconsolidation of Covestro reduced trade accounts receivable by €1,943 million. Changes in impairment losses on trade accounts receivable were as follows: (XLS:) Download Impairments of Trade Accounts Receivable 2016 2017 € million € million Accumulated impairment losses, January 1 (248) (408) Divestments / changes in the scope of consolidation – 41 Impairment losses in the reporting period (165) (133) Impairment loss reversals or utilization 35 29 Exchange differences (30) 46 Accumulated impairment losses, December 31 (408) (425) Trade accounts receivable amounting to €8,189 million (2016: €10,954 million) were not individually impaired. Of this amount, €1,440 million (2016: €1,161 million) was past due or due immediately on the closing date. The amounts of impaired and past-due trade accounts receivable are summarized in the following table: (XLS:) Download Impaired and Past-Due Trade Accounts Receivable Of which neither impaired nor past due at the closing date Of which unimpaired but past due at the closing date Of which impaired at the closing date Carrying amount€ million up to 3 months 3–6 months 6–12 months more than 12 months December 31, 2017 8,582 6,749 934 142 104 260 393 December 31, 2016 10,969 9,793 780 162 125 94 15 The gross carrying amount of individually impaired trade accounts receivable was €798 million (2016: €192 million). The impairment losses recognized on these assets totaled €405 million (2016: €177 million), resulting in a net carrying amount of €393 million (2016: €15 million). The unimpaired receivables were deemed to be collectible on the basis of established credit management processes and individual assessments of customer risks. Recognized impairment losses included an appropriate allowance for the default risk as of the end of the reporting period. Receivables from government health service institutions, especially in Greece, Italy, Portugal and Spain, are under special observation in view of the government debt crisis. Although there were no material defaults on such receivables in 2017 or 2016, it is possible that future developments in these countries could result in payment delays and / or defaults. This could necessitate the recognition of impairment losses due to new occurrences. Trade accounts receivable from government health service institutions in the above countries at the end of 2017 totaled €102 million (2016: €134 million). An excess-of-loss policy exists for the Pharmaceuticals, Consumer Health and Animal Health segments as part of a global credit insurance program. More than 80% of the receivables of these segments are insured up to a maximum total annual compensation payment of €150 million (2016: €150 million). A global excess-of-loss policy has also existed for the Crop Science segment since January 2016. In this global credit insurance program, more than 80% of this segment’s receivables are insured up to a maximum total annual compensation payment of €300 million (2016: €300 million). A further €696 million (2016: €743 million) of receivables was secured by advance payments, letters of credit or guarantees or by liens on land, buildings or harvest yields.