Notes to the consolidated financial statements of Aegon N.V.  Note 30 238 30.1 Real estate held for own use and equipment General account real estate held for own use are mainly held by Aegon USA and Aegon the Netherlands, with relatively smaller  holdings at Aegon Hungary and Aegon Spain. The carrying value under a historical cost model amounts to EUR 310 million  (2012: EUR 321 million). 37% of the value of the general account real estate held for own use was last revalued in 2013 (2012: 45%), based on market value  appraisals by qualified internal and external appraisers. 97% of the appraisals in 2013 were performed by independent external  appraisers (2012: 97%). General account real estate held for own use has not been pledged as security for liabilities, nor are there any restrictions on title.  Depreciation expenses are recorded in “Commissions and expenses” in the income statement. The useful lives of buildings range  between 40 and 50 years. None of the equipment is held for lease (2012: EUR 0 million). Equipment has not been pledged as security for liabilities, nor are there  any restrictions on title. Depreciation expenses have been recorded in “Commissions and expenses” in the income statement. Equipment  is generally depreciated over a period of three to five years. Annual Report 2013 Net book value General  account real  estate held  for own use Equipment Total At January 1, 2012 319 239 558 At December 31, 2012 307 214 521 At December 31, 2013 288 199 487 Cost At January 1, 2013 383 475 858 Additions - 65 65 Capitalized subsequent expenditure 3 - 3 Disposals (1) (62) (62) Unrealized gains/(losses) through equity (5) - (5) Net exchange differences (9) (11) (20) At December 31, 2013 370 468 838 Accumulated depreciation and impairment losses At January 1, 2013 76 261 337 Depreciation through income statement 8 58 66 Disposals - (46) (46) Impairment losses - 1 1 Net exchange differences (2) (5) (7) At December 31, 2013 82 269 351 Cost At January 1, 2012 390 488 878 Additions 2 59 61 Capitalized subsequent expenditure 2 - 2 Disposals (4) (71) (75) Unrealized gains/(losses) through equity (5) - (5) Net exchange differences (2) (1) (3) At December 31, 2012 383 475 858 Accumulated depreciation and impairment losses At January 1, 2012 71 249 320 Depreciation through income statement 8 67 75 Disposals (2) (63) (65) Impairment losses - 7 7 Net exchange differences (1) 1 - At December 31, 2012 76 261 337