Please answer the given financial question based on the context.
Context: notes to consolidated financial statements uncertain tax provisions as described in note 1 , the company adopted fin 48 on january 1 , 2007 . the effect of adopting fin 48 was not material to the company 2019s financial statements . the following is a reconciliation of the company 2019s beginning and ending amount of unrecognized tax benefits ( in millions ) . .
|balance at january 1 2007|$ 53|
|additions based on tax positions related to the current year|4|
|additions for tax positions of prior years|24|
|reductions for tax positions of prior years|-6 ( 6 )|
|settlements|-5 ( 5 )|
|balance at december 31 2007|$ 70|
of the amount included in the previous table , $ 57 million of unrecognized tax benefits would impact the effective tax rate if recognized . aon does not expect the unrecognized tax positions to change significantly over the next twelve months . the company recognizes interest and penalties related to unrecognized income tax benefits in its provision for income taxes . aon accrued potential penalties and interest of less than $ 1 million related to unrecognized tax positions during 2007 . in total , as of december 31 , 2007 , aon has recorded a liability for penalties and interest of $ 1 million and $ 7 million , respectively . aon and its subsidiaries file income tax returns in the u.s . federal jurisdiction as well as various state and international jurisdictions . aon has substantially concluded all u.s . federal income tax matters for years through 2004 . the internal revenue service commenced an examination of aon 2019s federal u.s . income tax returns for 2005 and 2006 in the fourth quarter of 2007 . material u.s . state and local income tax jurisdiction examinations have been concluded for years through 2002 . aon has concluded income tax examinations in its primary international jurisdictions through 2000 . aon corporation .
Question: what is the net change amount of unrecognized tax benefits during 2007 , ( in millions ) ?


Answer: The answer is:17.0