Non-current deferred tax assets are included in the caption Other assets on the consolidated balance sheets.
Non-current deferred tax liabilities are included in the caption Other long-term liabilities on the consolidated balance sheets.
In December 2017, the U. S.  government enacted comprehensive tax legislation commonly referred to as the Tax Cuts and Jobs Act of 2017 (Tax Reform Act).
The legislation significantly changes U. S.  tax law by, among other things, lowering corporate income tax rates, implementing a modified territorial tax system and imposing a transition tax on deemed repatriated earnings of foreign subsidiaries.
The Tax Reform Act permanently reduces the U. S.  corporate income tax rate from a maximum of 35% to a flat 21% rate, effective January 1, 2018.
ASC 740: Income Taxes, requires companies to recognize the effect of the tax law changes in the period of enactment.
However, the SEC staff issued Staff Accounting Bulletin 118 which will allow companies to record provisional amounts during a measurement period that is similar to the measurement period used when accounting for business combinations.
The Company has adjusted its deferred tax assets and liabilities based on the reduction of the U. S.  federal corporate tax rate from 35% to 21% and assessed the realizability of our deferred tax assets based on our current understanding of the provisions of the new law.
The Company considers its accounting for the impacts of the Tax Reform Act to be incomplete and the Company will continue to assess the impact of the Tax Reform Act (and expected further guidance from federal and state tax authorities as well as further guidance for the associated income tax accounting) on its business and consolidated financial statements over the next 12 months.
The Tax Reform Act eliminated the corporate alternative minimum tax (AMT) for tax years commencing on or after January 1, 2018.
As a result, AMT credit carryforwards may be utilized to reduce future income tax liabilities.
In addition, excess AMT credits are refundable in any taxable year beginning after 2017 and before 2022 in an amount equal to 50% (100% in the case of taxable years beginning in 2021) of the excess of the minimum tax credit for the taxable year over the amount of the credit allowable for the year against regular tax liability.
Accordingly, the Company has reclassified $16 million of AMT credit carry forwards as a non-current tax receivable.
As of December 30, 2017, substantially all of the Company’s U. S.  and foreign deferred tax assets, net of deferred tax liabilities, continued to be subject to a valuation allowance.
The realization of these assets is dependent on substantial future taxable income which at December 30, 2017, in management’s estimate, is not more likely than not to be achieved.
In 2017, gross deferred tax assets decreased by $1,018 million primarily for provisional decreases related to the remeasurement of deferred tax assets due to the 21% tax rate under the Tax Reform Act, as well as decreases related to acquired intangibles and goodwill, offset by a decrease in the gross deferred tax liability balance of $112 million primarily for provisional decreases related to the remeasurement of deferred tax liabilities due to the 21% tax rate under the Tax Reform Act, and a decrease in the gross valuation allowance of $905 million.
In 2016, the net valuation allowance decreased by $143 million primarily for decreases in deferred tax assets related to foreign capitalized research costs, acquired intangibles and goodwill.
In 2015, the net valuation allowance increased by $174 million primarily for increases in deferred tax assets related to the net operating losses generated from pre-tax book losses in the U. S.  The following is a summary of the Company’s various tax attribute carryforwards as of December 30, 2017.
## Table 0 ##
Utilization of $8 million of the Company’s U. S.  federal net operating loss carryforwards are subject to annual limitations as a result of the ATI Technologies ULC (ATI) acquisition.
Gas Sales and Deliveries O&R generally recovers the cost of the gas that it buys and then sells to its firm sales customers.
It does not make any margin or profit on the gas it sells.
O&R’s gas revenues are subject to a weather normalization clause.
Effective November 2009, O&R’s New York gas revenues (which accounted for substantially all of O&R’s gas revenues in 2009) became subject to a revenue decoupling mechanism.
As a result, its gas delivery revenues are generally not affected by changes in delivery volumes from levels assumed when rates were approved.
O&R’s gas deliveries and sales for the last five years wer
## Table 1 ##
For further discussion of the company’s gas operating revenues and its gas results, see “Results of Operations” in Item 7.
For additional segment information, see Note N to the financial statements in Item 8.
Gas Peak Demand The gas peak demand for firm service customers in O&R’s service area occurs during the winter heating season.
The daily peak day demand during the winter 2010/2011 (through January 31, 2011) occurred on January 23, 2011 when the demand reached 176 mdths.
The 2010/2011 winter demand included an estimated 87 mdths for O&R’s full-service customers and 89 mdths for customers participating in its gas retail access program.
“Design weather” for the gas system is a standard to which the actual peak demand is adjusted for evaluation and planning purposes.
The company estimates that under design weather conditions the 2011/2012 service area peak demand will be 224 mdths, including an estimated 110 mdths for its full-service customers and 114 mdths for its retail access customers.
The company forecasts average annual growth of the peak gas demand over the next five years at design conditions to be approximately 1.6 percent in the company’s service area.
The forecasted peak demand at design conditions does not include gas used by interruptible gas customers or in generating stations.
The company continues to monitor the potential impact on customer demand from the current economic condition
PART III ITEM 10.
DIRECTORS, EXECUTIVE OFFICERS AND CORPORATE GOVERNANCE For the information required by this Item 10, other than information with respect to our Executive Officers contained at the end of Part I, Item 1 of this report, see “Election Of Directors,” “Nominees for Election to the Board of Directors,” “Corporate Governance” and “Section 16(a) Beneficial Ownership Reporting Compliance,” in the Proxy Statement for our 2016 Annual Meeting, which information is incorporated herein by reference.
The Proxy Statement for our 2016 Annual Meeting will be filed within 120 days of the close of our year.
For the information required by this Item 10 with respect to our Executive Officers, see Part I, Item 1.  of this report.
ITEM 11.
EXECUTIVE COMPENSATION For the information required by this Item 11, see “Compensation Discussion and Analysis,” “Compensation Committee Report,” and “Executive Compensation” in the Proxy Statement for our 2016 Annual Meeting, which information is incorporated herein by reference.
ITEM 12.
SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT AND RELATED STOCKHOLDER MATTERS For the information required by this Item 12 with respect to beneficial ownership of our common stock, see “Security Ownership of Certain Beneficial Owners and Management” in the Proxy Statement for our 2016Annual Meeting, which information is incorporated herein by reference.
The following table sets forth certain information as of December 31, 2015 regarding our equity plans :
## Table 2 ##
ITEM 13.
CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS, AND DIRECTOR INDEPENDENCE For the information required by this Item 13, see “Certain Transactions” and “Corporate Governance” in the Proxy Statement for our 2016 Annual Meeting, which information is incorporated herein by reference.
ITEM 14.
PRINCIPAL ACCOUNTING FEES AND SERVICES For the information required by this Item 14, see “Audit and Non-Audit Fees” and “Audit Committee Pre-Approval Procedures” in the Proxy Statement for our 2016Annual Meeting, which information is incorporated herein by reference.

<table><tr><td>Carryforward</td><td>Federal</td><td>State /Provincial</td><td>Expiration</td></tr><tr><td></td><td colspan="2">(In millions)</td><td></td></tr><tr><td>U.S.-net operating loss carryovers</td><td>$7,254</td><td>$309</td><td>2018 to 2037</td></tr><tr><td>U.S.-credit carryovers</td><td>$394</td><td>$213</td><td>2018 to 2037</td></tr><tr><td>Canada-credit carryovers</td><td>$369</td><td>$42</td><td>2021 to 2037</td></tr><tr><td>Other foreign net operating loss carryovers</td><td>$37</td><td>N/A</td><td>various</td></tr></table>
<table><tr><td></td><td colspan="5"> Year Ended December 31,</td></tr><tr><td></td><td> 2006</td><td> 2007</td><td> 2008</td><td> 2009</td><td> 2010</td></tr><tr><td> Gas delivered (mdth)</td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Firm Sales</td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Full service</td><td>9,650</td><td>10,835</td><td>9,884</td><td>9,561</td><td>8,772</td></tr><tr><td>Firm transportation</td><td>9,058</td><td>10,248</td><td>10,471</td><td>10,905</td><td>10,692</td></tr><tr><td> Total Firm Sales and Transportation</td><td>18,708</td><td>21,083</td><td>20,355</td><td>20,466</td><td>19,464</td></tr><tr><td>Interruptible Sales</td><td>2,600</td><td>2,652</td><td>2,567</td><td>2,390</td><td>675</td></tr><tr><td> Total Gas Sold To O&R Customers</td><td>21,308</td><td>23,735</td><td>22,922</td><td>22,856</td><td>20,139</td></tr><tr><td>Transportation of customer-owned gas</td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Interruptible transportation</td><td>3,256</td><td>3,331</td><td>2,842</td><td>2,112</td><td>3,822</td></tr><tr><td>Sales for resale</td><td>939</td><td>1,044</td><td>1,007</td><td>953</td><td>840</td></tr><tr><td>Sales to electric generating stations</td><td>3,036</td><td>4,552</td><td>2,327</td><td>1,346</td><td>691</td></tr><tr><td>Off-System Sales</td><td>372</td><td>455</td><td>249</td><td>624</td><td>1</td></tr><tr><td> Total Sales and Transportation</td><td>28,911</td><td>33,117</td><td>29,347</td><td>27,891</td><td>25,493</td></tr><tr><td> Gas delivered ($ in millions)</td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Firm Sales</td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Full service</td><td>$166</td><td>$186</td><td>$172</td><td>$159</td><td>$131</td></tr><tr><td>Firm transportation</td><td>32</td><td>39</td><td>45</td><td>51</td><td>65</td></tr><tr><td> Total Firm Sales and Transportation</td><td>198</td><td>225</td><td>217</td><td>210</td><td>196</td></tr><tr><td>Interruptible Sales</td><td>28</td><td>25</td><td>27</td><td>21</td><td>9</td></tr><tr><td> Total Gas Sold To O&R Customers</td><td>226</td><td>250</td><td>244</td><td>231</td><td>205</td></tr><tr><td>Transportation of customer-owned gas</td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Sales to electric generating stations</td><td>3</td><td>3</td><td>4</td><td>2</td><td>—</td></tr><tr><td>Other operating revenues</td><td>7</td><td>12</td><td>10</td><td>9</td><td>13</td></tr><tr><td> Total Sales and Transportation</td><td>$236</td><td>$265</td><td>$258</td><td>$242</td><td>$218</td></tr><tr><td> Average Revenue Per dth Sold</td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Residential</td><td>$17.38</td><td>$17.31</td><td>$17.64</td><td>$16.86</td><td>$15.20</td></tr><tr><td>General</td><td>$16.44</td><td>$16.36</td><td>$16.55</td><td>$15.58</td><td>$13.64</td></tr></table>
<table><tr><td>Plan Category</td><td>Number of Securitiesto be Issued UponExercise ofOutstanding Options, Warrants and Rights (A)(B)</td><td>Weighted-AverageExercise Price ofOutstanding Options, Warrants and Rights</td><td>Number of SecuritiesRemaining Available forFuture Issuance UnderEquity CompensationPlans (ExcludingSecurities Reflected in Column (A)) (C)</td></tr><tr><td>Equity compensation plans approved by security holders</td><td>1,442,912</td><td>$86.98</td><td>4,446,967</td></tr></table>

Question: Which year is Full service for Gas delivered ($ in millions) the highest?
Answer: 2007