NOTES TO THE CONSOLIDATED FINANCIAL STATEMENTS Substantially all of the accounts receivable for the power segment are with government authorities. Refer to note 10 (b) and 10 (c) for further detail of credit risk and economic dependence. The utilities – water segment accounts receivable are composed of: Bristol Water is required to continue providing residential customers with water regardless of payment. NOTE 7. OTHER ASSETS As at December 31, 2013, based on a review of collection rates, $25,775 of trade receivables in the utilities – water segment were considered impaired and have been provided for (December 31, 2012 – $21,907). The increase in the provision for impairment of trade receivables at Bristol Water comprised: Charges for impaired receivables have been included in the consolidated statement of income as part of operating expenses.  The other classes within trade and other receivables do not contain impaired assets. Bristol Water has created an IAS 39 portfolio provision, but cannot identify which receivables are specifically impaired. Bristol Water policy is to consider the receivables impairment to be allocated on a collective basis and only impaired for the purposes of IFRS 7 disclosures when the loss can  be specifically identified with the receivable. The aging of net trade receivables at Bristol Water was: Dec 31, 2013 Dec 31, 2012 Trade receivables 46,795 39,181 Less: provision for impairment of receivables (25,775) (21,907) Net trade receivables 21,020 17,274 Other receivables 7,464 6,044 Accrued revenue 24,889 20,162 53,373 43,480 Dec 31, 2013 Dec 31, 2012 Past due 0-30 days 4,756 3,255 Past due 31-120 days 5,263 4,744 Past due more than 120 days 11,001 9,275 21,020 17,274 2013 2012 As at January 1 (21,907) (21,438) Charge to statement of income (5,954) (6,181) Amounts written off during the year as uncollectable 4,212 6,225 Net foreign exchange difference (2,126) (513) As at December 31 (25,775) (21,907) Dec 31, 2013 Dec 31, 2012 Prepaid expenses 5,855 3,665 Inventory of spare parts and consumable supplies, net  (1) 3,785 3,553 9,640 7,218 (1) Inventory as at December 31, 2013 is net of $370 provision for obsolescence (December 31, 2012 - $383). The cost of inventories recognized in operating expenses for the year ended December 31, 2013 was $6,419 (December 31, 2012 – $5,929). 70 CAPSTONE INFRASTRUCTURE CORPORATION