assessments are revised as conditions change and new information becomes available. We update our evaluations regularly, which can cause the valuation allowances to increase or decrease over time as such evaluations are revised. Negative credit migration, including an actual or expected increase in the level of problem loans, will result in an increase in the valuation allowance. Positive credit migration, including an actual or expected decrease in the level of problem loans, will result in a decrease in the valuation allowance. See Notes 1, 8 and 10 of the Notes to the Consolidated Financial Statements for information about how valuation allowances are established and monitored, activity in and balances of the valuation allowance, and the estimated fair value of impaired mortgage loans and related impairments included within net investment gains (losses) as of and for the years ended December 31, 2012, 2011 and 2010. We diversify our real estate investments by both geographic region and property type to reduce risk of concentration. Of our real estate investments, 83% were located in the United States, with the remaining 17% located outside the United States, at December 31, 2012. The three locations with the largest real estate investments were California, Japan and Florida at 20%, 14%, and 11%, respectively, at December 31, 2012. Real estate investments by type consisted of the following: Real Estate and Real Estate Joint Ventures We classify within traditional real estate our investment in income-producing real estate, which is comprised primarily of wholly-owned real estate and, to a much lesser extent, joint ventures with interests in single property income-producing real estate. The estimated fair value of the traditional real estate investment portfolio was $10.7 billion and $7.6 billion at December 31, 2012 and 2011, respectively. We classify within real estate joint ventures and funds, our investments in joint ventures with interests in multi-property projects with varying strategies ranging from the development of properties to the operation of income-producing properties, as well as our investments in real estate private equity funds. From time to time, we transfer investments from these joint ventures to traditional real estate, if we retain an interest in the joint venture after a completed property commences operations andwe intend to retain an interest in the property. Real estate and real estate joint venture investments by property type are categorized by sector as follows: We committed to acquire $2.9 billion and $1.1 billion of equity real estate during the years ended December 31, 2012 and 2011, respectively. Impairments recognized on real estate and real estate joint ventures were $20 million, $2 million and $49 million for the years ended December 31, 2012, 2011 and 2010, respectively. Depreciation expense on real estate investments was $168 million, $164 million and $151 million for the years ended December 31, 2012, 2011 and 2010, respectively. Real estate investments are net of accumulated depreciation of $1.3 billion at both December 31, 2012 and 2011. The carrying value of other limited partnership interests was $6.7 billion and $6.4 billion at December 31, 2012 and 2011 respectively, which included $1.4 billion and $1.1 billion of hedge funds, at December 31, 2012 and 2011, respectively. Other Limited Partnership Interests December 31, 2012 2011 Carrying Value %of Total Carrying Value %of Total (In millions) (In millions) Traditional .......................................................... $8,488 85.6% $5,836 68.2% Real estate joint ventures and funds ...................................... 941 9.5 2,340 27.3 Subtotal .......................................................... 9,429 95.1 8,176 95.5 Foreclosed (commercial, agricultural and residential) ......................... 488 4.9 264 3.1 Real estate held-for-investment ........................................ 9,917 100.0 8,440 98.6 Real estate held-for-sale ............................................... 1 — 123 1.4 Total real estate and real estate joint ventures ............................. $9,918 100.0% $8,563 100.0% December 31, 2012 2011 Carrying Value %of Total Carrying Value %of Total (In millions) (In millions) Office .............................................................. $5,789 58.4% $5,089 59.4% Apartment .......................................................... 1,717 17.3 1,610 18.8 Industrial ........................................................... 598 6.0 427 5.0 Real estate investment funds ............................................ 451 4.6 562 6.6 Retail .............................................................. 416 4.2 332 3.9 Hotel .............................................................. 372 3.7 218 2.5 Land .............................................................. 265 2.7 126 1.5 Agriculture .......................................................... 8 0.1 14 0.2 Other .............................................................. 302 3.0 185 2.1 Total real estate and real estate joint ventures .............................. $9,918 100.0% $8,563 100.0% MetLife, Inc. 46