39 annual report 2010 duke realty corporation | | related party transactions we provide property and asset management , leasing , construction and other tenant related services to unconsolidated companies in which we have equity interests . for the years ended december 31 , 2010 , 2009 and 2008 , respectively , we earned management fees of $ 7.6 million , $ 8.4 million and $ 7.8 million , leasing fees of $ 2.7 million , $ 4.2 million and $ 2.8 million and construction and development fees of $ 10.3 million , $ 10.2 million and $ 12.7 million from these companies . we recorded these fees based on contractual terms that approximate market rates for these types of services , and we have eliminated our ownership percentages of these fees in the consolidated financial statements . commitments and contingencies we have guaranteed the repayment of $ 95.4 million of economic development bonds issued by various municipalities in connection with certain commercial developments . we will be required to make payments under our guarantees to the extent that incremental taxes from specified developments are not sufficient to pay the bond debt service . management does not believe that it is probable that we will be required to make any significant payments in satisfaction of these guarantees . we also have guaranteed the repayment of secured and unsecured loans of six of our unconsolidated subsidiaries . at december 31 , 2010 , the maximum guarantee exposure for these loans was approximately $ 245.4 million . with the exception of the guarantee of the debt of 3630 peachtree joint venture , for which we recorded a contingent liability in 2009 of $ 36.3 million , management believes it probable that we will not be required to satisfy these guarantees . we lease certain land positions with terms extending to december 2080 , with a total obligation of $ 103.6 million . no payments on these ground leases are material in any individual year . we are subject to various legal proceedings and claims that arise in the ordinary course of business . in the opinion of management , the amount of any ultimate liability with respect to these actions will not materially affect our consolidated financial statements or results of operations . contractual obligations at december 31 , 2010 , we were subject to certain contractual payment obligations as described in the table below: .

payments due by period ( in thousands ) total: long-term debt ( 1 ): 5413606
lines of credit ( 2 ): 214225
share of debt of unconsolidated joint ventures ( 3 ): 447573
ground leases: 103563
operating leases: 2704
development and construction backlog costs ( 4 ): 521041
other: 1967
total contractual obligations: 6704679
payments due by period ( in thousands ) 2011: long-term debt ( 1 ): 629781
lines of credit ( 2 ): 28046
share of debt of unconsolidated joint ventures ( 3 ): 87602
ground leases: 2199
operating leases: 840
development and construction backlog costs ( 4 ): 476314
other: 1015
total contractual obligations: 1225797
payments due by period ( in thousands ) 2012: long-term debt ( 1 ): 548966
lines of credit ( 2 ): 9604
share of debt of unconsolidated joint ventures ( 3 ): 27169
ground leases: 2198
operating leases: 419
development and construction backlog costs ( 4 ): 44727
other: 398
total contractual obligations: 633481
payments due by period ( in thousands ) 2013: long-term debt ( 1 ): 725060
lines of credit ( 2 ): 176575
share of debt of unconsolidated joint ventures ( 3 ): 93663
ground leases: 2169
operating leases: 395
development and construction backlog costs ( 4 ): -
other: 229
total contractual obligations: 998091
payments due by period ( in thousands ) 2014: long-term debt ( 1 ): 498912
lines of credit ( 2 ): -
share of debt of unconsolidated joint ventures ( 3 ): 34854
ground leases: 2192
operating leases: 380
development and construction backlog costs ( 4 ): -
other: 90
total contractual obligations: 536428
payments due by period ( in thousands ) 2015: long-term debt ( 1 ): 473417
lines of credit ( 2 ): -
share of debt of unconsolidated joint ventures ( 3 ): 65847
ground leases: 2202
operating leases: 370
development and construction backlog costs ( 4 ): -
other: 54
total contractual obligations: 541890
payments due by period ( in thousands ) thereafter: long-term debt ( 1 ): 2537470
lines of credit ( 2 ): -
share of debt of unconsolidated joint ventures ( 3 ): 138438
ground leases: 92603
operating leases: 300
development and construction backlog costs ( 4 ): -
other: 181
total contractual obligations: 2768992

( 1 ) our long-term debt consists of both secured and unsecured debt and includes both principal and interest . interest expense for variable rate debt was calculated using the interest rates as of december 31 , 2010 . ( 2 ) our unsecured lines of credit consist of an operating line of credit that matures february 2013 and the line of credit of a consolidated subsidiary that matures july 2011 . interest expense for our unsecured lines of credit was calculated using the most recent stated interest rates that were in effect . ( 3 ) our share of unconsolidated joint venture debt includes both principal and interest . interest expense for variable rate debt was calculated using the interest rate at december 31 , 2010 . ( 4 ) represents estimated remaining costs on the completion of owned development projects and third-party construction projects. .

Questions:
what is the total long-term debt?
what are the total contractual obligations?
what fraction of total contractual obligations is long-term debt?
what percentage does this represent?

Answers:
5413606
6704679
0.807
80.7%