A detailed reconciliation of available for sale, trading securities and equity investments measured at fair value on a recurring basis using Level 3 inputs for the year ended December 31, 2009 follows.
## Table 0 ##
(**) Amounts attributable to unrealized gains or losses related to available for sale securities held at
## Table 1 ##
Interest income earned from trading securities totaled $61 million for 2009, $116 million for 2008 and $116 million for 2007.
These amounts are included in other interest income on the Consolidated Income Statement.
Nonrecurring Fair Value Changes We may be required to measure certain other financial assets at fair value on a nonrecurring basis.
These adjustments to fair value usually result from the application of lower-of-cost-or-fair value accounting or write-downs of individual assets due to impairment.
The amounts below for nonaccrual loans and loans held for sale represent the carrying value of loans for which adjustments are primarily based on the appraised value of collateral or based on an observable market price, which often results in significant management assumptions and input with respect to the determination of fair value.
The fair value determination of the equity investment resulting in an impairment loss included below was based on observable market data for other comparable entities as adjusted for internal assumptions and unobservable inputs.
The amounts below for commercial servicing rights reflect a recovery of a certain strata during 2009 while no strata were impaired at December 31, 2009 and two strata were impaired at December 31, 2008.
The fair value of commercial mortgage servicing rights is estimated by using an internal valuation model.
The model calculates the present value of estimated future net servicing cash flows considering estimates of servicing revenue and costs, discount rates and prepayment speeds.
Annually, this model is subject to an internal review process to validate controls and model results.
As of December 31, 2009 and 2008, we had a liability for uncertain tax positions excluding interest and penalties of $227 million and $257 million, respectively.
A reconciliation of the beginning and ending balance of unrecognized tax benefits is as follows: Changes in Unrecognized Tax Benefits
## Table 2 ##
(a) Includes $202 million acquired from National City.
(b) Includes $42 million acquired from Mercantile.
## Table 3 ##
Any changes in the amounts of unrecognized tax benefits related to temporary differences would result in a reclassification to deferred tax liability; any changes in the amounts of unrecognized tax benefits related to other permanent differences (per above table) would result in an adjustment to income tax expense and therefore our effective tax rate.
The unrecognized tax benefits related to other permanent items above that if recognized would affect the effective tax rate is $162 million.
This is less than the total amount of unrecognized tax benefit related to permanent differences because a portion of those unrecognized benefits relate to state tax matters.
It is reasonably possible that the liability for uncertain tax positions could increase or decrease in the next twelve months due to completion of tax authorities’ exams or the expiration of statutes of limitations.
Management estimates that the liability for uncertain tax positions could decrease by $44 million within the next twelve months.
The consolidated federal income tax returns of The PNC Financial Services Group, Inc.  and subsidiaries through 2003 have been audited by the Internal Revenue Service (IRS) and we have resolved all disputed matters through the IRS appeals division.
The IRS is currently examining the 2004 through 2006 consolidated federal income tax returns of The PNC Financial Services Group, Inc.  and subsidiaries and we expect that examination to conclude, with all adjustments being agreed to, in the first half of 2010.
We expect the IRS to begin its examination of our 2007 and 2008 consolidated federal income tax returns during 2010.
The consolidated federal income tax returns of National City through 2004 have been audited by the IRS and we have resolved all matters through the IRS Appeals division.
The formal closing agreement is not yet executed.
The IRS has completed field examination of the 2005 through 2007 consolidated federal income tax returns of National City and unresolved issues will be appealed.
We expect the 2008 federal income tax return to begin being audited later in 2010.
California, Delaware, District of Columbia, Florida, Illinois, Indiana, Maryland, Missouri, New Jersey, New York, and New York City are principally where we were subject to state and local income tax.
Audits currently in process for these states include: California (2003-2005), Illinois (2004-2007), Indiana (2004-2007), Missouri (2003-2005), New York (2001- 2006), and New York City (2005-2007).
In the ordinary course of business we are routinely subject to audit by the taxing authorities of states and at any given time a number of audits will be in process.
The years remaining open under the statute of limitations for assessing income taxes is 2006 or 2007 and later for most state and local jurisdictions.
Our policy is to classify interest and penalties associated with income taxes as income tax expense.
For 2009, we had net recoveries of $24 million of gross interest and penalties reducing income tax expense.
The total accrued interest and penalties at December 31, 2009 and December 31, 2008 was $144 million and $164 million, respectively.
constitutes an event of default under our other debt instruments, including our senior notes, and, therefore, our senior notes would also be subject to acceleration of maturity.
If such acceleration were to occur, we would not have sufficient liquidity available to repay the indebtedness.
We would likely have to seek an amendment under our Credit Facilities for relief from the financial covenants or repay the debt with proceeds from the issuance of new debt or equity, or asset sales, if necessary.
We may be unable to amend our Credit Facilities or raise sufficient capital to repay such obligations in the event the maturities are accelerated.
Financial assurance We must provide financial assurance to governmental agencies and a variety of other entities under applicable environmental regulations relating to our landfill operations for capping, closure and post-closure costs, and related to our performance under certain collection, landfill and transfer station contracts.
We satisfy these financial assurance requirements by providing surety bonds, letters of credit, or insurance policies (the Financial Assurance Instruments), or trust deposits, which are included in restricted cash and marketable securities and other assets in our consolidated balance sheets.
The amount of the financial assurance requirements for capping, closure and post-closure costs is determined by applicable state environmental regulations.
The financial assurance requirements for capping, closure and post-closure costs may be associated with a portion of the landfill or the entire landfill.
Generally, states require a third-party engineering specialist to determine the estimated capping, closure and post-closure costs that are used to determine the required amount of financial assurance for a landfill.
The amount of financial assurance required can, and generally will, differ from the obligation determined and recorded under U. S.  GAAP.
The amount of the financial assurance requirements related to contract performance varies by contract.
Additionally, we must provide financial assurance for our insurance program and collateral for certain performance obligations.
We do not expect a material increase in financial assurance requirements during 2014, although the mix of financial assurance instruments may change.
These financial instruments are issued in the normal course of business and are not considered indebtedness.
Because we currently have no liability for the Financial Assurance Instruments, they are not reflected in our consolidated balance sheets; however, we record capping, closure and post-closure liabilities and self-insurance liabilities as they are incurred.
The underlying obligations of the financial assurance instruments, in excess of those already reflected in our consolidated balance sheets, would be recorded if it is probable that we would be unable to fulfill our related obligations.
We do not expect this to occur.
Off-Balance Sheet Arrangements We have no off-balance sheet debt or similar obligations, other than financial assurance instruments and operating leases, that are not classified as debt.
We do not guarantee any third-party debt.
Free Cash Flow We define free cash flow, which is not a measure determined in accordance with U. S.  GAAP, as cash provided by operating activities less purchases of property and equipment, plus proceeds from sales of property and equipment as presented in our consolidated statements of cash flows.
Our free cash flow for the years ended December 31, 2013, 2012 and 2011 is calculated as follows (in millions of dollars):

['

Level 3 Instruments OnlyIn millions	Residential mortgage- backed agency	Residential mortgage- backed non-agency	Commercial mortgage- backed non-agency	Asset- backed	State and municipal	Other debt	Corporate stocks and other	Total available forsale securities
December 31, 2008	$3,304	$337	$833	$271	$34	$58	$4,837
National City acquisition	$7	899	59	50	48	1,063
January 1, 2009	7	4,203	337	892	321	82	58	5,900
Total realized/unrealized gains or losses:
Included in earnings (**)	-444	-6	-104	-9	-563
Included in other comprehensive income	-2	616	627	-22	-2	4	-6	1,215
Purchases, issuances, and settlements, net	-713	-253	-37	-23	-19	-5	-1,050
Transfers into Level 3, net	4,640	-699	525	-30	-5	4,431
December 31, 2009	$5	$8,302	$6	$1,254	$266	$53	$47	$9,933
(**) Amounts attributable to unrealized gains or losses related to available for salesecurities held at December 31, 2009:	$-444	$-6	$-104	$-9	$-563

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Level 3 Instruments OnlyIn millions	Trading securities debt	Trading securities equity	Equity investments - direct	Equity investments - indirect
December 31, 2008	$56	$17	$322	$249
National City acquisition	26	6	287	323
January 1, 2009	82	23	609	572
Total realized/unrealized gains or losses:
Included in earnings (**)	-3	1	-24	-20
Purchases, issuances, and settlements, net	8	-20	10	41
Transfers into Level 3, net	2	-4
December 31, 2009	$89	$—	$595	$593
(**) Amounts attributable to unrealized gains or losses related to trading securitiesand equity investments held at December 31, 2009:	$-33	$-19

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In millions	2009	2008	2007
Balance of gross unrecognized tax benefits at January 1	$257	$57	$49
Increases:
Positions taken during a prior period	22	203(a)	52(b)
Positions taken during the current period	26	1
Decreases:
Positions taken during a prior period	-39	-3	-2
Settlements with taxing authorities	-34	-39
Reductions resulting from lapse of statute of limitations	-5	-4
Balance of gross unrecognized tax benefits at December 31	$227	$257	$57

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December 31, 2009 – In millions	2009
Unrecognized tax benefits related to:
Acquired companies within measurement period:
Permanent differences	$5
Other:
Temporary differences	37
Permanent differences	185
Total	$227

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Question: As As the chart 0 shows,which year is the value of the Asset- backed securities on December 31 the lowest?
Answer: 2008