{"pre_text": ["15 .", "leases in january 1996 , the company entered into a lease agreement with an unrelated third party for a new corporate office facility , which the company occupied in february 1997 .", "in may 2004 , the company entered into the first amendment to this lease agreement , effective january 1 , 2004 .", "the lease was extended from an original period of 10 years , with an option for five additional years , to a period of 18 years from the inception date , with an option for five additional years .", "the company incurred lease rental expense related to this facility of $ 1.3 million in 2008 , 2007 and 2006 .", "the future minimum lease payments are $ 1.4 million per annum from january 1 , 2009 to december 31 , 2014 .", "the future minimum lease payments from january 1 , 2015 through december 31 , 2019 will be determined based on prevailing market rental rates at the time of the extension , if elected .", "the amended lease also provided for the lessor to reimburse the company for up to $ 550000 in building refurbishments completed through march 31 , 2006 .", "these amounts have been recorded as a reduction of lease expense over the remaining term of the lease .", "the company has also entered into various noncancellable operating leases for equipment and office space .", "office space lease expense totaled $ 9.3 million , $ 6.3 million and $ 4.7 million for the years ended december 31 , 2008 , 2007 and 2006 , respectively .", "future minimum lease payments under noncancellable operating leases for office space in effect at december 31 , 2008 are $ 8.8 million in 2009 , $ 6.6 million in 2010 , $ 3.0 million in 2011 , $ 1.8 million in 2012 and $ 1.1 million in 2013 .", "16 .", "royalty agreements the company has entered into various renewable , nonexclusive license agreements under which the company has been granted access to the licensor 2019s technology and the right to sell the technology in the company 2019s product line .", "royalties are payable to developers of the software at various rates and amounts , which generally are based upon unit sales or revenue .", "royalty fees are reported in cost of goods sold and were $ 6.3 million , $ 5.2 million and $ 3.9 million for the years ended december 31 , 2008 , 2007 and 2006 , respectively .", "17 .", "geographic information revenue to external customers is attributed to individual countries based upon the location of the customer .", "revenue by geographic area is as follows: ."], "post_text": ["."], "table": [["( in thousands )", "year ended december 31 , 2008", "year ended december 31 , 2007", "year ended december 31 , 2006"], ["united states", "$ 151688", "$ 131777", "$ 94282"], ["germany", "68390", "50973", "34567"], ["japan", "66960", "50896", "35391"], ["canada", "8033", "4809", "4255"], ["other european", "127246", "108971", "70184"], ["other international", "56022", "37914", "24961"], ["total revenue", "$ 478339", "$ 385340", "$ 263640"]], "table_ori": [["", "Year Ended December 31,"], ["<i>(in thousands)</i>", "2008", "2007", "2006"], ["United States", "$151,688", "$131,777", "$94,282"], ["Germany", "68,390", "50,973", "34,567"], ["Japan", "66,960", "50,896", "35,391"], ["Canada", "8,033", "4,809", "4,255"], ["Other European", "127,246", "108,971", "70,184"], ["Other international", "56,022", "37,914", "24,961"], ["Total revenue", "$478,339", "$385,340", "$263,640"]]}

Question: what is the total combined royalty fees for years ended 2006-2008 , in millions?
Evidence:
text_15: royalty fees are reported in cost of goods sold and were $ 6.3 million , $ 5.2 million and $ 3.9 million for the years ended december 31 , 2008 , 2007 and 2006 , respectively .
Program: add(6.3, 5.2), add(#0, 3.9)
Answer:
str_answer: 15.4
exe_answer: 15.4