between the Company and Citibank.
See Note 7 for further discussion of this transaction and the related commitment.
Legal Proceedings From time to time, BlackRock receives subpoenas or other requests for information from various U. S.  federal, state governmental and regulatory authorities in connection with certain industry-wide or other investigations or proceedings.
It is BlackRock’s policy to fully cooperate with such inquiries.
The Company and certain of its subsidiaries have been named as defendants in various legal actions, including arbitrations and other litigation arising in connection with BlackRock’s activities.
Additionally, certain of the investment funds that the Company manages are subject to lawsuits, any of which could potentially harm the investment returns of the applicable fund or result in the Company being liable to the funds for any resulting damages.
Management, after consultation with legal counsel, currently does not anticipate that the aggregate liability, if any, arising out of regulatory matters or lawsuits will have a material adverse effect on BlackRock’s earnings, financial position, or cash flows although, at the present time, management is not in a position to determine whether any such pending or threatened matters will have a material adverse effect on BlackRock’s results of operations in any future reporting period.
Indemnifications In the ordinary course of business, BlackRock enters into contracts pursuant to which it may agree to indemnify third parties in certain circumstances.
The terms of these indemnities vary from contract to contract and the amount of indemnification liability, if any, cannot be determined.
Under the Transaction Agreement in the MLIM Trans action, the Company has agreed to indemnify Merrill Lynch for losses it may incur arising from (1) any alleged or actual breach, failure to comply, violation or other deficiency with respect to any regulatory or fiduciary requirements relating to the operation of BlackRock’s business, (2) any fees or expenses incurred or owed by BlackRock to any brokers, financial advisors or comparable other persons retained or employed by BlackRock in connection with the MLIM Transaction, and (3) certain specified tax covenants.
Management believes that the likelihood of any liability arising under these indemnification provisions is remote.
Management cannot estimate any potential maximum exposure due both to the remoteness of any potential claims and the fact that items that would be included within any such calculated claim would be beyond the control of BlackRock.
Consequently, no liability has been recorded on the consolidated statements of financial condition.13.
STOCK-BASED COMPENSATION The components of the Company’s stock-based compensation expense are comprised of the following: Year ended December 31
## Table 0 ##
Stock Award and Incentive Plan Pursuant to the BlackRock, Inc.  1999 Stock Award and Incentive Plan (the “Award Plan”), options to purchase shares of the Company’s common stock at an exercise price not less than the market value of BlackRock’s common stock on the date of grant in the form of stock options, restricted stock or RSUs may be granted to employees and non-employee directors.
A maximum of 17,000,000 shares of common stock are authorized for issuance under the Award Plan.
Of this amount, 4,381,646 shares remain available for future awards at December 31, 2008.
Upon exercise of employee stock options, the issuance of restricted stock or the vesting of RSUs, the Company issues shares out of treasury, to the extent available.
Stock Options Stock option grants were made to certain employees pursuant to the Award Plan in 1999 through 2003.
Options granted have a ten-year life, vest ratably over periods ranging from two to five years and become exercisable upon vesting.
Prior to the January 2007 grant described below, the Company had not granted any stock options since 2003.
Stock option activity for the years ended December 31, 2008, 2007 and 2006 is summarized below.
The following tabular reconciliation presents the total amounts of gross unrecognized tax benefits:
## Table 1 ##
Included in the balance of unrecognized tax benefits at December 31, 2011, 2010 and 2009, respectively, are $226 million, $194 million and $184 million of tax benefits that, if recognized, would affect the effective tax rate.
The Company recognizes interest and penalties related to income tax matters as a component of income tax expense.
Related to the unrecognized tax benefits noted above, the Company accrued interest and penalties of $10 million during 2011 and in total, as of December 31, 2011, had recognized a liability for interest and penalties of $66 million.
The Company accrued interest and penalties of $8 million during 2010 and in total, as of December 31, 2010, had recognized a liability for interest and penalties of $56 million.
During 2009, the Company accrued interest and penalties of $8 million and in total, as of December 31, 2009, has recognized a liability for interest and penalties of $48 million, of which $28 million was assumed in the BGI Transaction.
Pursuant to the Amended and Restated Stock Purchase Agreement, the Company has been indemnified by Barclays for $69 million of unrecognized tax benefits.
BlackRock is subject to U. S.  federal income tax, state and local income tax, and foreign income tax in multiple jurisdictions.
Tax years after 2007 remain open to U. S.  federal income tax examination, tax years after 2002 remain open to state and local income tax examination, and tax years after 2006 remain open to income tax examination in the United Kingdom.
With few exceptions, as of December 31, 2011, the Company is no longer subject to U. S.  federal, state, local or foreign examinations by tax authorities for years before 2003.
The Internal Revenue Service (“IRS”) completed its examination of BlackRock’s 2006 and 2007 tax years in March 2011.
In November 2011, the IRS commenced its examination of BlackRock’s 2008 and 2009 tax years, and while the impact on the Company’s consolidated financial statements is undetermined, it is not expected to be material.
In July 2011, the IRS commenced its federal income tax audit of the BGI group, which BlackRock acquired in December 2009.
The tax years under examination are 2007 through December 1, 2009, and while the impact on the Company’s consolidated financial statements is undetermined, it is not expected to be material.
The Company is currently under audit in several state and local jurisdictions.
The significant state and local income tax examinations are in New York State and City for tax years 2006 through 2008, and New Jersey for tax years 2003 through 2009.
No state and local income tax audits cover years earlier than 2006 except for New Jersey.
No state and local income tax audits are expected to result in an assessment material to BlackRock’s consolidated financial statements.
In December 2009, Her Majesty’s Revenue and Customs (“HMRC”) commenced its U. K.  income tax audit of BlackRock’s 2007 through 2010 tax years.
While the impact on the Company’s consolidated financial statements is undetermined, it is not expected to be material.
As of December 31, 2011, it is reasonably possible the total amounts of unrecognized tax benefits will increase or decrease within the next 12 months due to completion of tax authorities’ exams or the expiration of statues of limitations.
Management estimates that the existing liability for uncertain tax positions could decrease by approximately $35 million to $50 million within the next 12 months.
The Company does not anticipate that any possible adjustments resulting from these audits would result in a material change to its consolidated financial statements.
For each period presented, the non-GAAP adjustments, including the PNC LTIP funding obligation, U. K.  lease exit costs and contribution to STIFs were tax effected at the respective blended rates applicable to the adjustments.
Amounts for 2013 included a tax benefit of approximately $48 million recognized in connection with the Charitable Contribution.
The tax benefit has been excluded from net income attributable to BlackRock, Inc. , as adjusted due to the nonrecurring nature of the Charitable Contribution.
Non-GAAP adjustments for 2014, 2013 and 2012 reflected the revaluation of deferred income tax liabilities related to intangible assets and/or goodwill.
The amount for 2014 included a $9 million net noncash tax benefit arising primarily from state and local income tax changes.
The amount for 2013 included a $69 million noncash tax benefit, primarily related to legislation enacted in the United Kingdom and state and local income tax changes.
The amount for 2012 included a $50 million noncash tax benefit, primarily related to the effect of legislation enacted in the United Kingdom and the state and local income tax effect resulting from changes in the Company’s organizational structure.
Such amounts for 2014, 2013 and 2012 have been excluded from as adjusted results as they will not have a cash flow impact and to ensure comparability among periods presented.
(4) Amounts for 2012 exclude net income attributable to participating securities (see below).
(5) Nonvoting participating preferred stock is considered to be a common stock equivalent for purposes of determining basic and diluted earnings per share calculations.
Prior to 2013, certain unvested RSUs were not included in diluted weighted-average common shares outstanding as they were deemed participating securities.
Average outstanding participating securities were 0.2 million in 2012.
For further information, see Note 21, Earnings per Share, to the consolidated financial statements.
Assets Under Management AUM for reporting purposes generally is based upon how investment advisory and administration fees are calculated for each portfolio.
Net asset values, total assets, committed assets or other measures may be used to determine portfolio AUM.
AUM and Net Inflows (Outflows) by Client Type
## Table 2 ##
AUM and Net Inflows (Outflows) by Product Type
## Table 3 ##
(1) Amounts include the effect of two single client low-fee institutional index fixed income outflows of $36.0 billion and $74.2 billion.
(2) Advisory AUM represents long-term portfolio liquidation assignments.
Outflows include planned client distributions.
(3) Amounts include commodity iShares.
Gain on business divestitures and impairments, net We strive to have a number one or number two market position in each of the markets we serve, or have a clear path on how we will achieve a leading market position over time.
Where we cannot establish a leading market position, or where operations are not generating acceptable returns, we may decide to divest certain assets and reallocate resources to other markets.
Asset or business divestitures could result in gains, losses or asset impairment charges that may be material to our results of operations in a given period.
During 2018, we recorded a net gain on business divestitures, net of asset impairments of $44.9 million.
During 2017, we recorded a net gain on business divestitures, net of asset impairments of $27.1 million.
We also recorded a gain on business divestitures of $6.8 million due to the transfer of ownership of the landfill gas collection and control system and the remaining post-closure and environmental liabilities associated with one of our divested landfills.
During 2016, we recorded a charge to earnings of $4.6 million primarily related to environmental costs associated with one of our divested landfills.
During 2016, we also recorded a net gain related to a business divestiture of $4.7 million.
Restructuring Charges In January 2018, we eliminated certain positions following the consolidation of select back-office functions, including but not limited to the integration of our National Accounts support functions into our existing corporate support functions.
These changes include a reduction in administrative staffing and the closure of certain office locations.
During 2018, we incurred restructuring charges of $26.4 million that primarily consisted of severance and other employee termination benefits, the closure of offices with non-cancelable lease agreements, and the redesign of our back-office functions and upgrades to certain of our software systems.
We paid $24.7 million during 2018 related to these restructuring efforts.
In January 2016, we realigned our field support functions by combining our three regions into two field groups, consolidating our areas and streamlining select operational support roles at our Phoenix headquarters.
Additionally, in the second quarter of 2016, we began the redesign of our back-office functions as well as the consolidation of over 100 customer service locations into three Customer Resource Centers.
The redesign of our back-office functions and upgrades to certain of our software systems continued into 2018.
During the years ended December 31, 2017 and 2016, we incurred $17.6 million and $40.7 million of restructuring charges, respectively, that primarily consisted of severance and other employee termination benefits, transition costs, relocation benefits, and the closure of offices with lease agreements with non-cancelable terms.
The savings realized from these restructuring efforts have been reinvested in our customer-focused programs and initiatives.
Interest Expense The following table provides the components of interest expense, including accretion of debt discounts and accretion of discounts primarily associated with environmental and risk insurance liabilities assumed in acquisitions (in millions of dollars):

<table><tr><td></td><td colspan="3"> Year ended December 31,</td></tr><tr><td></td><td> 2008</td><td> 2007</td><td> 2006</td></tr><tr><td>Stock-based compensation:</td><td></td><td></td><td></td></tr><tr><td>Restricted stock and RSUs</td><td>$209</td><td>$122</td><td>$48</td></tr><tr><td>Stock options</td><td>10</td><td>13</td><td>13</td></tr><tr><td>Long-term incentive plans funded by PNC</td><td>59</td><td>53</td><td>50</td></tr><tr><td>ESPP and other</td><td>—</td><td>—</td><td>9</td></tr><tr><td>Total stock-based compensation</td><td>$278</td><td>$188</td><td>$120</td></tr></table>
<table><tr><td></td><td colspan="3">Year ended December 31,</td></tr><tr><td>  <i>(Dollar amounts in millions)</i> </td><td>2011</td><td>2010</td><td>2009</td></tr><tr><td>Balance at January 1</td><td>$307</td><td>$285</td><td>$114</td></tr><tr><td>Additions for tax positions of prior years</td><td>22</td><td>10</td><td>11</td></tr><tr><td>Reductions for tax positions of prior years</td><td>-1</td><td>-17</td><td>-1</td></tr><tr><td>Additions based on tax positions related to current year</td><td>46</td><td>35</td><td>63</td></tr><tr><td>Lapse of statute of limitations</td><td>—</td><td>-8</td><td>—</td></tr><tr><td>Settlements</td><td>-25</td><td>-2</td><td>-16</td></tr><tr><td>Foreign exchange translation</td><td>—</td><td>—</td><td>-3</td></tr><tr><td>Positions assumed in BGI Transaction</td><td>—</td><td>4</td><td>117</td></tr><tr><td>Balance at December 31</td><td>$349</td><td>$307</td><td>$285</td></tr></table>
<table><tr><td></td><td colspan="3"> AUM</td><td colspan="3">Net Inflows (Outflows)</td></tr><tr><td> <i>(in millions)</i> </td><td> 2014</td><td> 2013</td><td> 2012</td><td>2014</td><td>2013</td><td>2012 -1</td></tr><tr><td>Retail</td><td>$534,329</td><td>$487,777</td><td>$403,484</td><td>$54,944</td><td>$38,804</td><td>$11,556</td></tr><tr><td><i>iShares</i></td><td>1,024,228</td><td>914,372</td><td>752,706</td><td>100,601</td><td>63,971</td><td>85,167</td></tr><tr><td>Institutional:</td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Active</td><td>959,160</td><td>932,410</td><td>884,695</td><td>-10,420</td><td>-928</td><td>-24,046</td></tr><tr><td>Index</td><td>1,816,124</td><td>1,677,650</td><td>1,441,481</td><td>36,128</td><td>15,266</td><td>-75,142</td></tr><tr><td>Institutional subtotal</td><td>2,775,284</td><td>2,610,060</td><td>2,326,176</td><td>25,708</td><td>14,338</td><td>-99,188</td></tr><tr><td> Long-term</td><td>4,333,841</td><td>4,012,209</td><td>3,482,366</td><td>181,253</td><td>117,113</td><td>-2,465</td></tr><tr><td>Cash management</td><td>296,353</td><td>275,554</td><td>263,743</td><td>25,696</td><td>10,056</td><td>5,048</td></tr><tr><td>Advisory<sup>-2</sup></td><td>21,701</td><td>36,325</td><td>45,479</td><td>-13,173</td><td>-7,442</td><td>-74,540</td></tr><tr><td> Total</td><td>$4,651,895</td><td>$4,324,088</td><td>$3,791,588</td><td>$193,776</td><td>$119,727</td><td>$-71,957</td></tr></table>
<table><tr><td></td><td colspan="3"> AUM</td><td colspan="3">Net Inflows (Outflows)</td></tr><tr><td> <i>(in millions)</i> </td><td> 2014</td><td> 2013</td><td> 2012</td><td>2014</td><td>2013</td><td>2012 -1</td></tr><tr><td>Equity</td><td>$2,451,111</td><td>$2,317,695</td><td>$1,845,501</td><td>$52,420</td><td>$69,257</td><td>$54,016</td></tr><tr><td>Fixed income</td><td>1,393,653</td><td>1,242,186</td><td>1,259,322</td><td>96,406</td><td>11,508</td><td>-66,829</td></tr><tr><td>Multi-asset</td><td>377,837</td><td>341,214</td><td>267,748</td><td>28,905</td><td>42,298</td><td>15,817</td></tr><tr><td>Alternatives</td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Core</td><td>88,006</td><td>85,026</td><td>68,367</td><td>3,061</td><td>2,703</td><td>-3,922</td></tr><tr><td>Currency and commodities<sup>-3</sup></td><td>23,234</td><td>26,088</td><td>41,428</td><td>461</td><td>-8,653</td><td>-1,547</td></tr><tr><td>Subtotal</td><td>111,240</td><td>111,114</td><td>109,795</td><td>3,522</td><td>-5,950</td><td>-5,469</td></tr><tr><td> Long-term</td><td>4,333,841</td><td>4,012,209</td><td>3,482,366</td><td>181,253</td><td>117,113</td><td>-2,465</td></tr><tr><td>Cash management</td><td>296,353</td><td>275,554</td><td>263,743</td><td>25,696</td><td>10,056</td><td>5,048</td></tr><tr><td>Advisory<sup>-2</sup></td><td>21,701</td><td>36,325</td><td>45,479</td><td>-13,173</td><td>-7,442</td><td>-74,540</td></tr><tr><td> Total</td><td>$4,651,895</td><td>$4,324,088</td><td>$3,791,588</td><td>$193,776</td><td>$119,727</td><td>$-71,957</td></tr></table>

Question: Which year is AUM Active the most? (in year)
Answer: 2014