the goldman sachs group , inc .and subsidiaries notes to consolidated financial statements long-term debt instruments the aggregate contractual principal amount of long-term other secured financings for which the fair value option was elected exceeded the related fair value by $ 361 million and $ 362 million as of december 2016 and december 2015 , respectively .the aggregate contractual principal amount of unsecured long-term borrowings for which the fair value option was elected exceeded the related fair value by $ 1.56 billion and $ 1.12 billion as of december 2016 and december 2015 , respectively .the amounts above include both principal- and non-principal-protected long-term borrowings .impact of credit spreads on loans and lending commitments the estimated net gain attributable to changes in instrument-specific credit spreads on loans and lending commitments for which the fair value option was elected was $ 281 million for 2016 , $ 751 million for 2015 and $ 1.83 billion for 2014 , respectively .the firm generally calculates the fair value of loans and lending commitments for which the fair value option is elected by discounting future cash flows at a rate which incorporates the instrument-specific credit spreads .for floating-rate loans and lending commitments , substantially all changes in fair value are attributable to changes in instrument-specific credit spreads , whereas for fixed-rate loans and lending commitments , changes in fair value are also attributable to changes in interest rates .debt valuation adjustment the firm calculates the fair value of financial liabilities for which the fair value option is elected by discounting future cash flows at a rate which incorporates the firm 2019s credit spreads .the net dva on such financial liabilities was a loss of $ 844 million ( $ 544 million , net of tax ) for 2016 and was included in 201cdebt valuation adjustment 201d in the consolidated statements of comprehensive income .the gains/ ( losses ) reclassified to earnings from accumulated other comprehensive loss upon extinguishment of such financial liabilities were not material for 2016 .note 9 .loans receivable loans receivable is comprised of loans held for investment that are accounted for at amortized cost net of allowance for loan losses .interest on loans receivable is recognized over the life of the loan and is recorded on an accrual basis .the table below presents details about loans receivable. .
[['$ in millions', 'as of december 2016', 'as of december 2015'], ['corporate loans', '$ 24837', '$ 20740'], ['loans to private wealth management clients', '13828', '13961'], ['loans backed by commercial real estate', '4761', '5271'], ['loans backed by residential real estate', '3865', '2316'], ['other loans', '2890', '3533'], ['total loans receivable gross', '50181', '45821'], ['allowance for loan losses', '-509 ( 509 )', '-414 ( 414 )'], ['total loans receivable', '$ 49672', '$ 45407']]
as of december 2016 and december 2015 , the fair value of loans receivable was $ 49.80 billion and $ 45.19 billion , respectively .as of december 2016 , had these loans been carried at fair value and included in the fair value hierarchy , $ 28.40 billion and $ 21.40 billion would have been classified in level 2 and level 3 , respectively .as of december 2015 , had these loans been carried at fair value and included in the fair value hierarchy , $ 23.91 billion and $ 21.28 billion would have been classified in level 2 and level 3 , respectively .the firm also extends lending commitments that are held for investment and accounted for on an accrual basis .as of december 2016 and december 2015 , such lending commitments were $ 98.05 billion and $ 93.92 billion , respectively .substantially all of these commitments were extended to corporate borrowers and were primarily related to the firm 2019s relationship lending activities .the carrying value and the estimated fair value of such lending commitments were liabilities of $ 327 million and $ 2.55 billion , respectively , as of december 2016 , and $ 291 million and $ 3.32 billion , respectively , as of december 2015 .as of december 2016 , had these lending commitments been carried at fair value and included in the fair value hierarchy , $ 1.10 billion and $ 1.45 billion would have been classified in level 2 and level 3 , respectively .as of december 2015 , had these lending commitments been carried at fair value and included in the fair value hierarchy , $ 1.35 billion and $ 1.97 billion would have been classified in level 2 and level 3 , respectively .goldman sachs 2016 form 10-k 147 .

Question: what percentage of total loans receivable gross in 2015 were loans backed by commercial real estate?
Answer: 12%