CITI HOLDINGS Citi Holdings contains businesses and portfolios of assets that Citigroup has determined are not central to its core Citicorp business.
These noncore businesses tend to be more asset-intensive and reliant on wholesale funding and also may be product-driven rather than client-driven.
Citi intends to exit these businesses as quickly as practicable yet in an economically rational manner through business divestitures, portfolio run-off and asset sales.
Citi has made substantial progress divesting and exiting businesses from Citi Holdings, having completed 15 divestitures in 2009, including Smith Barney, Nikko Cordial Securities, Nikko Asset Management Financial Institution Credit Card business (FI) and Diners Club North America.
Citi Holdings’ assets have been reduced by nearly 40%, or $351 billion, from the peak level of $898 billion in the first quarter of 2008 to $547 billion at year-end 2009.
Citi Holdings’ assets represented less than 30% of Citi’s assets as of December 31, 2009.
Asset reductions from Citi Holdings have the combined benefits of further fortifying Citigroup’s capital base, lowering risk, simplifying the organization and allowing Citi to allocate capital to fund long-term strategic businesses.
Citi Holdings consists of the following businesses: Brokerage and Asset Management; Local Consumer Lending; and Special Asset Pool.
With Citi’s exit from the loss-sharing agreement with the U. S.  government in December 2009, the Company conducted a broad review of the Citi Holdings asset base to determine which assets are strategically important to Citicorp.
As a result of this analysis, approximately $61 billion of assets will be moved from Citi Holdings into Citicorp in the first quarter of 2010.
The assets consist primarily of approximately $34 billion of U. S.  mortgages that will be transferred to NA RCB, approximately $19 billion of commercial and corporate loans and securities related to core Citicorp clients, of which approximately $17 billion will be moved to S&B and the remainder to NA RCB, and approximately $5.0 billion of assets related to Citi’s Mexico asset management business that will be moved to LATAM RCB.
## Table 0 ##
CAPITAL RESOURCES AND LIQUIDITY CAPITAL RESOURCES Overview Capital has historically been generated by earnings from Citi’s operating businesses.
Citi may also augment its capital through issuances of common stock, convertible preferred stock, preferred stock, equity issued through awards under employee benefit plans, and, in the case of regulatory capital, through the issuance of subordinated debt underlying trust preferred securities.
In addition, the impact of future events on Citi’s business results, such as corporate and asset dispositions, as well as changes in accounting standards, also affect Citi’s capital levels.
Generally, capital is used primarily to support assets in Citi’s businesses and to absorb market, credit, or operational losses.
While capital may be used for other purposes, such as to pay dividends or repurchase common stock, Citi’s ability to utilize its capital for these purposes is currently restricted due to its agreements with the U. S.  government, generally for so long as the U. S.  government continues to hold Citi’s common stock or trust preferred securities.
See also “Supervision and Regulation” below.
Citigroup’s capital management framework is designed to ensure that Citigroup and its principal subsidiaries maintain sufficient capital consistent with Citi’s risk profile and all applicable regulatory standards and guidelines, as well as external rating agency considerations.
The capital management process is centrally overseen by senior management and is reviewed at the consolidated, legal entity, and country level.
Senior management is responsible for the capital management process mainly through Citigroup’s Finance and Asset and Liability Committee (FinALCO), with oversight from the Risk Management and Finance Committee of Citigroup’s Board of Directors.
The FinALCO is composed of the senior-most management of Citigroup for the purpose of engaging management in decision-making and related discussions on capital and liquidity matters.
Among other things, FinALCO’s responsibilities include: determining the financial structure of Citigroup and its principal subsidiaries; ensuring that Citigroup and its regulated entities are adequately capitalized in consultation with its regulators; determining appropriate asset levels and return hurdles for Citigroup and individual businesses; reviewing the funding and capital markets plan for Citigroup; and monitoring interest rate risk, corporate and bank liquidity, and the impact of currency translation on non-U.
S.  earnings and capital.
Capital Ratios Citigroup is subject to the risk-based capital guidelines issued by the Federal Reserve Board.
Historically, capital adequacy has been measured, in part, based on two risk-based capital ratios, the Tier 1 Capital and Total Capital (Tier 1 Capital + Tier 2 Capital) ratios.
Tier 1 Capital consists of the sum of “core capital elements,” such as qualifying common stockholders’ equity, as adjusted, qualifying noncontrolling interests, and qualifying mandatorily redeemable securities of subsidiary trusts, principally reduced by goodwill, other disallowed intangible assets, and disallowed deferred tax assets.
Total Capital also includes “supplementary” Tier 2 Capital elements, such as qualifying subordinated debt and a limited portion of the allowance for credit losses.
Both measures of capital adequacy are stated as a percentage of risk-weighted assets.
Further, in conjunction with the conduct of the 2009 Supervisory Capital Assessment Program (SCAP), U. S.  banking regulators developed a new measure of capital termed “Tier 1 Common,” which has been defined as Tier 1 Capital less non-common elements, including qualifying perpetual preferred stock, qualifying noncontrolling interests, and qualifying mandatorily redeemable securities of subsidiary trusts.
Citigroup’s risk-weighted assets are principally derived from application of the risk-based capital guidelines related to the measurement of credit risk.
Pursuant to these guidelines, on-balance-sheet assets and the credit equivalent amount of certain off-balance-sheet exposures (such as financial guarantees, unfunded lending commitments, letters of credit, and derivatives) are assigned to one of several prescribed risk-weight categories based upon the perceived credit risk associated with the obligor, or if relevant, the guarantor, the nature of the collateral, or external credit ratings.
Risk-weighted assets also incorporate a measure for market risk on covered trading account positions and all foreign exchange and commodity positions whether or not carried in the trading account.
Excluded from risk-weighted assets are any assets, such as goodwill and deferred tax assets, to the extent required to be deducted from regulatory capital.
See “Components of Capital Under Regulatory Guidelines” below.
Citigroup is also subject to a Leverage ratio requirement, a non-risk-based measure of capital adequacy, which is defined as Tier 1 Capital as a percentage of quarterly adjusted average total assets.
To be “well capitalized” under federal bank regulatory agency definitions, a bank holding company must have a Tier 1 Capital ratio of at least 6%, a Total Capital ratio of at least 10%, and a Leverage ratio of at least 3%, and not be subject to a Federal Reserve Board directive to maintain higher capital levels.
The following table sets forth Citigroup’s regulatory capital ratios as of December 31, 2009 and December 31, 2008.
## Table 1 ##
As noted in the table above, Citigroup was “well capitalized” under the federal bank regulatory agency definitions at year end for both 2009 and 2008.
The following table summarizes the consolidated statements of cash flows for the years ended December 31, 2017, 2016 and 2015:
## Table 2 ##
Operating Activities Cash flows from operating activities for the year ended December 31, 2017 primarily consisted of payments received from our clients and interest earned on funds held for clients.
Cash used in operating activities primarily consisted of cash we invested in personnel and expenditures made to support the growth and infrastructure of our business.
These payments included costs of operations, advertising and other sales and marketing efforts, IT infrastructure development, product research and development and security and administrative costs.
Compared to the year ended December 31, 2016, our operating cash flows for the year ended December 31, 2017 were positively impacted by the growth of our business.
Cash flows from operating activities for the year ended December 31, 2016 primarily consisted of payments received from our clients and interest earned on funds held for clients.
Cash used in operating activities primarily consisted of cash we invested in personnel and expenditures made to support the growth and infrastructure of our business.
These payments included costs of operations, sales and marketing efforts, IT infrastructure development and security and administrative costs.
Compared to the year ended December 31, 2015, our operating cash flows for the year ended December 31, 2016 were positively impacted by the growth of our business.
Investing Activities Cash flows from investing activities for the year ended December 31, 2017 changed by $85.3 million due to the impact of changes in funds held for clients and a $15.6 million increase in cash used for purchases of property and equipment, primarily as a result of the ongoing construction of our fourth headquarters building.
Cash flows from investing activities for the year ended December 31, 2016 changed by $152.7 million due to the impact of changes in funds held for clients and a $27.3 million increase in cash used for purchases of property and equipment, primarily as a result of the construction of our third headquarters building.
Financing Activities Cash flows from financing activities for the year ended December 31, 2017 changed by $30.1 million due to the impact of changes in client funds obligation, which is due to the timing of receipts from our clients and payments to our client’s employees.
Financing cash flows were also impacted by the $35.9 million increase in proceeds from the issuance of long-term debt.
These cash flows provided by financing activities were partially offset by the $34.3 million increase in payments on long-term debt related to our previous loan agreements, a $21.3 million increase in open market purchases of common stock, an $18.5 million increase in withholding taxes paid related to net share settlements, $0.8 million in debt extinguishment costs and a $0.3 million increase in the payment of debt issuance costs.

<table><tr><td>In millions of dollars</td><td>2009</td><td>2008</td><td>2007</td><td>% Change 2009 vs. 2008</td><td>% Change 2008 vs. 2007</td></tr><tr><td>Net interest revenue</td><td>$17,314</td><td>$22,459</td><td>$21,797</td><td>-23%</td><td>3%</td></tr><tr><td>Non-interest revenue</td><td>13,321</td><td>-29,157</td><td>-2,284</td><td>NM</td><td>NM</td></tr><tr><td>Total revenues, net of interest expense</td><td>$30,635</td><td>$-6,698</td><td>$19,513</td><td>NM</td><td>NM</td></tr><tr><td>Provisions for credit losses and for benefits and claims</td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Net credit losses</td><td>$24,660</td><td>$14,070</td><td>$7,230</td><td>75%</td><td>95%</td></tr><tr><td>Credit reserve build</td><td>5,457</td><td>11,444</td><td>5,836</td><td>-52</td><td>96</td></tr><tr><td>Provision for loan losses</td><td>$30,117</td><td>$25,514</td><td>$13,066</td><td>18%</td><td>95%</td></tr><tr><td>Provision for benefits and claims</td><td>1,210</td><td>1,396</td><td>919</td><td>-13</td><td>52</td></tr><tr><td>Provision for unfunded lending commitments</td><td>109</td><td>-172</td><td>71</td><td>NM</td><td>NM</td></tr><tr><td>Total provisions for credit losses and for benefits and claims</td><td>$31,436</td><td>$26,738</td><td>$14,056</td><td>18%</td><td>90%</td></tr><tr><td>Total operating expenses</td><td>$14,677</td><td>$25,197</td><td>$20,487</td><td>-42%</td><td>23%</td></tr><tr><td>(Loss) from continuing operations before taxes</td><td>$-15,478</td><td>$-58,633</td><td>$-15,030</td><td>74%</td><td>NM</td></tr><tr><td>Benefits for income taxes</td><td>-7,239</td><td>-22,621</td><td>-6,338</td><td>68</td><td>NM</td></tr><tr><td>Income (loss) from continuing operations</td><td>$-8,239</td><td>$-36,012</td><td>$-8,692</td><td>77%</td><td>NM</td></tr><tr><td>Net income attributable to noncontrolling interests</td><td>27</td><td>-372</td><td>218</td><td>NM</td><td>NM</td></tr><tr><td>Citi Holdings net (loss)</td><td>$-8,266</td><td>$-35,640</td><td>$-8,910</td><td>77%</td><td>NM</td></tr><tr><td>Balance sheet data(in billions of dollars)</td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Total EOP assets</td><td>$547</td><td>$715</td><td>$888</td><td>-23%</td><td>-19%</td></tr><tr><td>Total EOP deposits</td><td>$92</td><td>$83</td><td>$79</td><td>11%</td><td>5%</td></tr></table>
<table><tr><td>At year end</td><td>2009</td><td>2008</td></tr><tr><td>Tier 1 Common</td><td>9.60%</td><td>2.30%</td></tr><tr><td>Tier 1 Capital</td><td>11.67</td><td>11.92</td></tr><tr><td>Total Capital (Tier 1 Capital and Tier 2 Capital)</td><td>15.25</td><td>15.70</td></tr><tr><td>Leverage</td><td>6.89</td><td>6.08</td></tr></table>
<table><tr><td></td><td colspan="3">Year Ended December 31,</td><td rowspan="2">$ Change 2017 vs 2016</td><td rowspan="2">% Change 2017 vs 2016</td><td rowspan="2">$ Change 2016 vs 2015</td><td rowspan="2">% Change 2016 vs 2015</td></tr><tr><td></td><td>2017</td><td>2016</td><td>2015</td></tr><tr><td>Net cash provided by (used in):</td><td colspan="3">(in thousands)</td><td></td><td></td><td></td><td></td></tr><tr><td>Operating activities</td><td>$130,600</td><td>$98,953</td><td>$42,972</td><td>$31,647</td><td>32%</td><td>$55,981</td><td>130%</td></tr><tr><td>Investing activities</td><td>-290,346</td><td>-205,051</td><td>-52,324</td><td>-85,295</td><td>42%</td><td>-152,727</td><td>292%</td></tr><tr><td>Financing activities</td><td>145,665</td><td>115,542</td><td>34,922</td><td>30,123</td><td>26%</td><td>80,620</td><td>231%</td></tr><tr><td>Net change in cash and cash equivalents</td><td>$-14,081</td><td>$9,444</td><td>$25,570</td><td>$-23,525</td><td>-249%</td><td>$-16,126</td><td>-63%</td></tr></table>

Question: Which year has the greatest proportion of Net interest revenue?
Answer: 2008