celanese corporation and subsidiaries notes to consolidated financial statements ( continued ) 2022 amend certain material agreements governing bcp crystal 2019s indebtedness ; 2022 change the business conducted by celanese holdings and its subsidiaries ; and 2022 enter into hedging agreements that restrict dividends from subsidiaries . in addition , the senior credit facilities require bcp crystal to maintain the following financial covenants : a maximum total leverage ratio , a maximum bank debt leverage ratio , a minimum interest coverage ratio and maximum capital expenditures limitation . the maximum consolidated net bank debt to adjusted ebitda ratio , as defined , previously required under the senior credit facilities , was eliminated when the company amended the facilities in january 2005 . as of december 31 , 2005 , the company was in compliance with all of the financial covenants related to its debt agreements . the maturation of the company 2019s debt , including short term borrowings , is as follows : ( in $ millions ) .
what is average of the debt maturities that will occur in the period from 2006 to 2010 in millions
( 1 ) includes $ 2 million purchase accounting adjustment to assumed debt . 17 . benefit obligations pension obligations . pension obligations are established for benefits payable in the form of retirement , disability and surviving dependent pensions . the benefits offered vary according to the legal , fiscal and economic conditions of each country . the commitments result from participation in defined contribution and defined benefit plans , primarily in the u.s . benefits are dependent on years of service and the employee 2019s compensation . supplemental retirement benefits provided to certain employees are non-qualified for u.s . tax purposes . separate trusts have been established for some non-qualified plans . defined benefit pension plans exist at certain locations in north america and europe . as of december 31 , 2005 , the company 2019s u.s . qualified pension plan represented greater than 85% ( 85 % ) and 75% ( 75 % ) of celanese 2019s pension plan assets and liabilities , respectively . independent trusts or insurance companies administer the majority of these plans . actuarial valuations for these plans are prepared annually . the company sponsors various defined contribution plans in europe and north america covering certain employees . employees may contribute to these plans and the company will match these contributions in varying amounts . contributions to the defined contribution plans are based on specified percentages of employee contributions and they aggregated $ 12 million for the year ended decem- ber 31 , 2005 , $ 8 million for the nine months ended december 31 , 2004 , $ 3 million for the three months ended march 31 , 2004 and $ 11 million for the year ended december 31 , 2003 . in connection with the acquisition of cag , the purchaser agreed to pre-fund $ 463 million of certain pension obligations . during the nine months ended december 31 , 2004 , $ 409 million was pre-funded to the company 2019s pension plans . the company contributed an additional $ 54 million to the non-qualified pension plan 2019s rabbi trusts in february 2005 . in connection with the company 2019s acquisition of vinamul and acetex , the company assumed certain assets and obligations related to the acquired pension plans . the company recorded liabilities of $ 128 million for these pension plans . total pension assets acquired amounted to $ 85 million. .