AMERICAN TOWER CORPORATION AND SUBSIDIARIES NOTES TO CONSOLIDATED FINANCIAL STATEMENTS—(Continued) Asset Retirement Obligations—The Company complies with the provisions of SFAS No.143, “Accounting for Asset Retirement Obligations” (SFAS No.143) and the provisions of Financial Accounting Standards Board (FASB) Interpretation No.47 “Accounting for Conditional Asset Retirement Obligations” (FIN No.47).
Both pronouncements address the financial accounting and reporting requirements for conditional obligations associated with the Company’s legal obligation to retire tangible long-lived assets and the related asset retirement costs.
The fair value of a liability for asset retirement obligations is recognized in the period in which it is incurred and can be reasonably estimated.
Such asset retirement costs are capitalized as part of the carrying amount of the related long-lived asset and depreciated over the asset’s estimated useful life.
Fair value estimates of liabilities for asset retirement obligations generally involve discounting of estimated future cash flows.
Periodic accretion of such liabilities due to the passage of time is recorded as an operating expense.
The Company has certain legal obligations related to tower assets which fall within the scope of SFAS No.143 and FIN No.47, principally obligations to remediate leased land on which certain of the Company’s tower assets are located.
The significant assumptions used in estimating the Company’s aggregate asset retirement obligation are: timing of tower removals; cost of tower removals; timing and number of land lease renewals; expected inflation rates; and creditadjusted risk-free interest rates that approximate the Company’s incremental borrowing rate.
The adoption of FIN No.47 primarily resulted in the acceleration of settlement date assumptions, as FIN No.47 precludes the Company from considering non-contractual lease renewal periods in determining its settlement date assumptions.
The Company adopted the provisions of SFAS No.143 as of January 1, 2003 and the provisions of FIN No.47 as of December 31, 2005.
Upon adoption of the provisions of FIN No.47, the Company recognized a $35.5 million charge (net of an $11.7 million tax benefit) as a cumulative effect of a change in accounting principle in the consolidated statement of operations for the year ended December 31, 2005.
In addition, the adoption of FIN No.47 resulted in an increase to the tower assets included in property and equipment, net of $66.9 million.
Had the Company adopted the provisions of FIN No.47 as of January 1, 2004, the aggregate asset retirement obligation as of January 1, 2004 and December 31, 2004 would have approximated $92.9 million and $99.5 million, respectively.
Had the Company adopted the provisions of FIN No.47 in prior periods, net loss for the year ended December 31, 2004 would have been approximately $(0.3) million and basic and diluted net loss per share for the year ended December 31, 2004 would have been approximately $(1.17).
The Company’s asset retirement obligation is included in other long-term liabilities in the accompanying consolidated balance sheets.
The changes in the carrying value of the Company’s asset retirement obligations for years ended December 31, 2006, 2005 and 2004 are as follows (in thousands):
## Table 0 ##
Fair Value of Financial Instruments—The carrying values of the Company’s financial instruments, with the exception of long-term obligations, including current portion, reasonably approximate the related fair values as of December 31, 2006 and 2005.
As of December 31, 2006, the carrying amount and fair value of long-term obligations, including current portion, were $3.5 billion and $4.1 billion, respectively.
As of December 31, 2005, the carrying amount and fair value of long-term obligations, including current portion, were $3.6 billion and
Table of Contents E*TRADE | 2016 10-K 24 ?
Limits on the persons who may call special meetings of stockholders ?
The prohibition of stockholder action by written consent ?
Advance notice requirements for nominations to the Board or for proposing matters that can be acted on by stockholders at stockholder meetings In addition, certain provisions of our stock incentive plans, management retention and employment agreements (including severance payments and stock option acceleration), our senior secured credit facility, certain provisions of Delaware law and certain provisions of the indentures governing certain series of our debt securities that would require us to offer to purchase such securities at a premium in the event of certain changes in our ownership may also discourage, delay or prevent someone from acquiring or merging with us, which could limit the opportunity for our stockholders to receive a premium for their shares of our common stock and could also affect the price that some investors are willing to pay for our common stock.
ITEM 1B.
UNRESOLVED STAFF COMMENTS None.
ITEM 2.
PROPERTIES A summary of our significant locations at December 31, 2016 is shown in the following table.
Square footage amounts are net of space that has been sublet or space that is part of a facility restructuring.
## Table 1 ##
All facilities are leased at December 31, 2016.
All other leased facilities with space of less than 25,000 square feet are not listed by location.
In addition to the significant facilities above, we also lease all 30 regional branches, ranging in space from approximately 2,500 to 8,000 square feet.
ITEM 3.
LEGAL PROCEEDINGS Information in response to this item can be found under the heading Legal Matters in Note 21— Commitments, Contingencies and Other Regulatory Matters in this Annual Report and is incorporated by reference into this item.
ITEM 4.
MINE SAFETY DISCLOSURES Not applicable.
Table of Contents E*TRADE | 2016 10-K 56 Off-Balance Sheet Arrangements We enter into various off-balance sheet arrangements in the ordinary course of business, primarily to meet the needs of our customers and to reduce our own exposure to interest rate risk.
These arrangements include firm commitments to extend credit.
Additionally, we enter into guarantees and other similar arrangements as part of transactions in the ordinary course of business.
For additional information on these arrangements, see Note 21—Commitments, Contingencies and Other Regulatory Matters within Item 8.
Financial Statements and Supplementary Data.
Contractual Obligations and Commitments The following table summarizes our contractual obligations at December 31, 2016 and the effect such obligations are expected to have on our liquidity and cash flow in future periods (dollars in millions):
## Table 2 ##
(1) Includes annual interest based on the contractual features of each security, using market rates at December 31, 2016.
Interest rates are assumed to remain at current levels over the life of all adjustable rate instruments.
(2) For subordinated debentures, does not assume early redemption under current conversion provisions.
(3) Includes annual interest payments.
Does not assume conversion for the non-interest bearing convertible debentures due 2019.
(4) Does not include sweep deposits, savings deposits, money market or checking deposits as there are no stated maturity dates and/or scheduled contractual payments.
(5) Includes future minimum lease payments, net of sublease proceeds under sale-leaseback transaction and operating leases with initial or remaining terms in excess of one year.
(6) Includes material purchase obligations for goods and services covered by non-cancelable contracts and contracts with termination clauses.
Includes contracts through the termination date, even if the contract is renewable.
At December 31, 2016, the Company had approximately $18 million of unused lines of credit available to customers under HELOCs, the majority of which expire in 2017.
The Company also had $83 million in unfunded commitments to fund partnerships, companies and other similar entities, including tax credit partnerships and community development related entities, which are not required to be consolidated, at December 31, 2016.
Additional information related to commitments and contingent liabilities is detailed in Note 21—Commitments, Contingencies and Other Regulatory Matters.
RISK MANAGEMENT As a financial services company, our business is exposed to certain risks.
The identification, mitigation and management of existing and potential risks is critical to effective enterprise risk management.
There are certain risks inherent to our industry (e. g.  execution of transactions) and certain risks that will surface through the conduct of our business operations.
We seek to monitor and manage our significant risk exposures by operating under a set of Board-approved limits and by monitoring certain risk indicators.
Our governance framework requires regular reporting on metrics, significant risks and exposures to senior management and the Board of Directors.
Our risk management framework, as described below, is in compliance with all applicable requirements.
We have a Board-approved Enterprise Risk Appetite Statement (RAS) that is provided to all employees.
The RAS specifies significant risk exposures and addresses the Company's tolerance of those risks, which are categorized as follows, with further information provided below

<table><tr><td></td><td>2006</td><td> 2005 </td><td> 2004 </td></tr><tr><td>Beginning balance as of January 1,</td><td>$164,222</td><td>$23,464</td><td>$4,635</td></tr><tr><td>(Deductions), additions and revisions in estimated cash flows, net of settlements</td><td>-710</td><td>2,587</td><td>17,016</td></tr><tr><td>Accretion expense</td><td>11,468</td><td>3,069</td><td>1,813</td></tr><tr><td>Liability assumed in merger with SpectraSite, Inc.</td><td></td><td>21,126</td><td></td></tr><tr><td>Increase due to change in accounting principle</td><td></td><td>113,976</td><td></td></tr><tr><td>Balance as of December 31,</td><td>$174,980</td><td>$164,222</td><td>$23,464</td></tr></table>
<table><tr><td>Location</td><td>Approximate Square Footage</td></tr><tr><td>Alpharetta, Georgia</td><td>260,000</td></tr><tr><td>Jersey City, New Jersey</td><td>109,000</td></tr><tr><td>Arlington, Virginia</td><td>102,000</td></tr><tr><td>Sandy, Utah</td><td>85,000</td></tr><tr><td>Menlo Park, California</td><td>63,000</td></tr><tr><td>New York, New York</td><td>52,000</td></tr><tr><td>Chicago, Illinois</td><td>37,000</td></tr></table>
<table><tr><td></td><td colspan="5">Payments Due by Period</td></tr><tr><td></td><td>Less Than 1 Year</td><td>1-3 Years</td><td>3-5 Years</td><td>Thereafter</td><td>Total</td></tr><tr><td>Trust preferred securities<sup>-1(2)</sup></td><td>15</td><td>29</td><td>29</td><td>601</td><td>674</td></tr><tr><td>Corporate debt<sup>-3</sup></td><td>50</td><td>104</td><td>101</td><td>1,062</td><td>1,317</td></tr><tr><td>Uncertain tax positions</td><td>7</td><td>10</td><td>6</td><td>5</td><td>28</td></tr><tr><td>Certificates of deposit<sup>-1(4)</sup></td><td>23</td><td>6</td><td>4</td><td>—</td><td>33</td></tr><tr><td>Leases<sup>-5</sup></td><td>27</td><td>53</td><td>39</td><td>37</td><td>156</td></tr><tr><td>Purchase obligations<sup>-6</sup></td><td>96</td><td>56</td><td>3</td><td>—</td><td>155</td></tr><tr><td>Total contractual obligations</td><td>$218</td><td>$258</td><td>$182</td><td>$1,705</td><td>$2,363</td></tr></table>

Question: What is the average amount of Arlington, Virginia of Approximate Square Footage, and Corporate debt of Payments Due by Period Thereafter ?
Answer: 51531