AMERICAN TOWER CORPORATION AND SUBSIDIARIES NOTES TO CONSOLIDATED FINANCIAL STATEMENTS The valuation allowance increased from $47.8 million as of December 31, 2009 to $48.2 million as of December 31, 2010.
The increase was primarily due to valuation allowances on foreign loss carryforwards.
At December 31, 2010, the Company has provided a valuation allowance of approximately $48.2 million which primarily relates to state net operating loss carryforwards, equity investments and foreign items.
The Company has not provided a valuation allowance for the remaining deferred tax assets, primarily its federal net operating loss carryforwards, as management believes the Company will have sufficient taxable income to realize these federal net operating loss carryforwards during the twenty-year tax carryforward period.
Valuation allowances may be reversed if related deferred tax assets are deemed realizable based on changes in facts and circumstances relevant to the assets’ recoverability.
The recoverability of the Company’s remaining net deferred tax asset has been assessed utilizing projections based on its current operations.
The projections show a significant decrease in depreciation in the later years of the carryforward period as a result of a significant portion of its assets being fully depreciated during the first fifteen years of the carryforward period.
Accordingly, the recoverability of the net deferred tax asset is not dependent on material improvements to operations, material asset sales or other non-routine transactions.
Based on its current outlook of future taxable income during the carryforward period, management believes that the net deferred tax asset will be realized.
The Company’s deferred tax assets as of December 31, 2010 and 2009 in the table above do not include $122.1 million and $113.9 million, respectively, of excess tax benefits from the exercises of employee stock options that are a component of net operating losses.
Total stockholders’ equity as of December 31, 2010 will be increased by $122.1 million if and when any such excess tax benefits are ultimately realized.
At December 31, 2010, the Company had net federal and state operating loss carryforwards available to reduce future federal and state taxable income of approximately $1.2 billion, including losses related to employee stock options of $0.3 billion.
If not utilized, the Company’s net operating loss carryforwards expire as follows (in thousands):
## Table 0 ##
In addition, the Company has Mexican tax credits of $5.2 million which if not utilized would expire in 2017.
Auction rate securities are securities that are structured with short-term reset dates of generally less than 90 days but with maturities in excess of 90 days.
At the end of the reset period, investors can sell or continue to hold the securities at par.
These securities are classified in the table below based on their legal stated maturity dates.
The following table summarizes the final maturities of our investments in debt securities as of March 31, 2006 (amounts in thousands):
## Table 1 ##
For the year ended March 31, 2006, net realized gains on investments consisted of $4.3 million of gross realized gains and no gross realized losses.
For the year ended March 31, 2005, net realized gains on investments consisted of $471,000 of gross realized gains and no gross realized losses.
For the year ended March 31, 2004, net realized gains on investments consisted of $25,000 of gross realized gains and $4,000 of gross realized losses.
In accordance with EITF 03-1, “The Meaning of Other-Than-Temporary Impairment and Its Application to Certain Investments,” the fair value of investments in an unrealized loss position for which an other-thantemporary impairment has not been recognized was $672.4 million and $508.2 million at March 31, 2006 and 2005, respectively, with related gross unrealized losses of $5.5 million and $4.1 million, respectively.
At March 31, 2006, the gross unrealized losses were comprised mostly of unrealized losses on U. S.  agency issues, corporate bonds, and mortgage-backed securities with $3.9 million of unrealized loss being in a continuous unrealized loss position for twelve months or greater.
At March 31, 2005, the gross unrealized losses were comprised mostly of unrealized losses on corporate bonds, U. S.  agency issues, and asset-backed securities with $464,000 of unrealized loss being in a continuous unrealized loss position for twelve months or greater.
The Company’s investment portfolio usually consists of government and corporate securities with effective maturities less than 30 months.
The longer the term of the securities, the more susceptible they are to changes in market rates of interest and yields on bonds.
Investments are reviewed periodically to identify possible impairment.
When evaluating the investments, the Company reviews factors such as the length of time and extent to which fair value has been below cost basis, the financial condition of the issuer, and the Company’s ability and intent to hold the investment for a period of time which may be sufficient for anticipated recovery in market value.
The Company has the intent and ability to hold these securities for a reasonable period of time sufficient for a forecasted recovery of fair value up to (or beyond) the initial cost of the investment.
The Company expects to realize the full value of all of these investments upon maturity or sale.5.
Software Development Costs and Intellectual Property Licenses As of March 31, 2006, capitalized software development costs included $45.0 million of internally developed software costs and $15.6 million of payments made to third-party software developers.
As of March 31, 2005, capitalized software development costs included $61.3 million of internally developed software costs and $30.3 million of payments made to third-party software developers.
Capitalized intellectual property licenses were $87.0 million and $35.7 million as of March 31, 2006 and 2005, respectively.
Amortization and write-offs of capitalized software development costs and intellectual property licenses, combined, was $173.6 million, $134.8 million, and $87.9 million for the years ended March 31, 2006, 2005, and 2004, respectively.
Amortization and write-offs of capitalized software development costs and intellectual property licenses for the year ended March 31, 2006 included product cancellation charges, exclusive of termination fees, of $10.3 million, impairment charges of $8.8 million, and recoverability write-offs of $3.8 million.
The combined portfolio is administered by, and related management services are provided by, CECONY (for itself and as agent for O&R) and costs are allocated between the Utilities in accordance with provisions approved by the NYSPSC.
See Note S to the financial statements in Item 8.
Charges from suppliers for the firm purchase of gas, which are based on formulas or indexes or are subject to negotiation, are generally designed to approximate market prices.
The gas supply contracts are for various terms extending to 2015.
The Utilities have contracts with interstate pipeline companies for the purchase of firm transportation from upstream points where gas has been purchased to the Utilities’ distribution systems, and for upstream storage services.
Charges under these transportation and storage contracts are approved by the FERC.
Such contracts are for various terms extending to 2027.
The Utilities are required to pay certain fixed charges under the supply, transportation and storage contracts whether or not the Steam Sales and Deliveries CECONY’s steam sales and deliveries for the last five years were contracted capacity is actually used.
These fixed charges amounted to approximately $270 million in 2013, including $230 million for CECONY.
See “Contractual Obligation s” below.
In addition, the Utilities purchase gas on the spot market and contract for interruptible gas transportation.
See “Recoverable Energy Costs” in Note A to the financial statements in Item 8.
Steam Operations Steam Facilities CECONY’s capitalized costs for utility plant, net of accumulated depreciation for steam facilities were $1,790 million and $1,674 million at December 31, 2013 and 2012, respectively.
CECONY generates steam at one steam-electric generating station and five steam-only generating stations and distributes steam to its customers through approximately 105 miles of transmission, distribution, and service piping.
## Table 2 ##
For further discussion of the company’s steam operating revenues and its steam results, see “Results of Operations” in Item 7.
For additional segment information, see Note N to the financial statements in Item 8.
Steam Peak Demand and Capacity Demand for steam in CECONY’s service area peaks during the winter heating season.
The one-hour peak demand during the winter of 2013/2014 (through January 31, 2014) occurred on January 23, 2014 when the demand reached 8.9 MMlbs per hour.
The company’s estimate for the winter of 2014/2015 peak demand of its steam customers is 9.3 MMlbs per hour under design criteria, which assumes severe weather.
On December 31, 2013, the steam system had the capability of delivering approximately 11.7 MMlbs of steam per hour, and CECONY estimates that the system will have the capability to deliver 11.7 MMlbs of steam per hour in the 2014/2015 winter.
Steam Supply Thirty-six percent of the steam produced by CECONY in 2013 was supplied by the company’s steam-only generating assets; 47 percent was produced by the company’s steam-electric generating assets, where steam and electricity are primarily cogenerated; and 17 percent was purchased under an agreement with Brooklyn Navy Yard Cogeneration Partners L. P.  O&R Electric Operations Electric Facilities O&R’s capitalized costs for utility plant, net of accumulated depreciation, for distribution facilities were $781 million an
HOST HOTELS & RESORTS, INC. , HOST HOTELS & RESORTS, L. P. , AND SUBSIDIARIES NOTES TO CONSOLIDATED FINANCIAL STATEMENTS—(Continued) contracts.
These contracts are marked-to-market with changes in fair value recorded to other comprehensive income (loss).
We recorded a loss of $14 million and a gain of $6 million for the years ended December 31, 2017 and 2016, respectively.
The foreign currency forward sale contracts are valued based on the forward yield curve of the foreign currency to U. S.  dollar forward exchange rate on the date of measurement.
We also evaluate counterparty credit risk when we calculate the fair value of the derivatives.
During 2017, in connection with the maturity of a foreign currency forward purchase contract with a total HOST HOTELS & RESORTS, INC. , HOST HOTELS & RESORTS, L. P. , AND SUBSIDIARIES NOTES TO CONSOLIDATED FINANCIAL STATEMENTS¡ª(Continued) contracts.
These contracts are marked-to-market with changes in fair value recorded to other comprehensive income (loss).
We recorded a loss of $14 million and a gain of $6 million for the years ended December 31, 2017 and 2016, respectively.
The foreign currency forward sale contracts are valued based on the forward yield curve of the foreign currency to U. S.  dollar forward exchange rate on the date of measurement.
We also evaluate counterparty credit risk when we calculate the fair value of the derivatives.
During 2017, in connection with the maturity of a foreign currency forward purchase contract with a total notional amount of €15 million, for which we received total proceeds of approximately $4 million, we entered into a new foreign currency forward purchase contract with the same notional amount.
We also made payments totaling approximately $2 million to settle forward currency hedges with a total notional amount of NZ$45 million and €55 million.
The gain or loss related to the matured contracts is initially included in accumulated other comprehensive income and is recognized in earnings when the hedged investment has been repatriated.
In addition to the foreign currency forward sale contracts, we have designated $129 million of the foreign currency draws on our credit facility as hedges of net investments in foreign operations.
Changes in fair value of the designated credit facility draws are recorded to foreign currency translation and other comprehensive income (loss) of unconsolidated affiliates.
We recorded a loss of $14 million and a gain of $2 million for the years ended December 31, 2017 and 2016, respectively.
Impairment During 2017, we recorded an impairment loss of $43 million related to the W New York.
The fair value was based on the expected sale proceeds of the property, which is considered an unobservable input (Level 3) in the GAAP fair value hierarchy.
The fair value of the property on December 31, 2017, following the impairment loss, was $191 million.
The property was classified as held-for-sale as of December 31, 2017.
Other Liabilities Fair Value of Other Financial Liabilities.
We did not elect the fair value measurement option for any of our other financial liabilities.
The fair values of secured debt and our credit facility are determined based on the expected future payments discounted at risk-adjusted rates.
Senior notes are valued based on quoted market prices.
The fair values of financial instruments not included in this table are estimated to be equal to their carrying amounts.
The fair value of certain financial liabilities is shown below (in millions):

<table><tr><td>Years ended December 31,</td><td>Federal</td><td>State</td><td>Foreign</td></tr><tr><td>2011 to 2015</td><td>$—</td><td>$—</td><td>$503</td></tr><tr><td>2016 to 2020</td><td>—</td><td>331,315</td><td>5,509</td></tr><tr><td>2021 to 2025</td><td>774,209</td><td>576,780</td><td>—</td></tr><tr><td>2026 to 2030</td><td>423,398</td><td>279,908</td><td>92,412</td></tr><tr><td>Total</td><td>$1,197,607</td><td>$1,188,003</td><td>$98,424</td></tr></table>
<table><tr><td> </td><td> Amortized Cost</td><td> Fair Value</td></tr><tr><td>Due in one year or less</td><td>$412,677</td><td>$410,504</td></tr><tr><td>Due after one year through two years</td><td>169,967</td><td>167,740</td></tr><tr><td>Due after two years through three years</td><td>—</td><td>—</td></tr><tr><td>Due in three years or more</td><td>17,156</td><td>16,557</td></tr><tr><td></td><td>599,800</td><td>594,801</td></tr><tr><td>Asset-backed securities</td><td>72,005</td><td>71,499</td></tr><tr><td>Total investments in debt securities</td><td>$671,805</td><td>$666,300</td></tr></table>
<table><tr><td></td><td colspan="5">Year Ended December 31,</td></tr><tr><td></td><td> 2009</td><td> 2010</td><td>2011</td><td>2012</td><td>2013</td></tr><tr><td> Steam Sold (MMlbs)</td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>General</td><td>544</td><td>515</td><td>519</td><td>425</td><td>547</td></tr><tr><td>Apartment house</td><td>6,725</td><td>5,748</td><td>5,779</td><td>5,240</td><td>6,181</td></tr><tr><td>Annual power</td><td>15,748</td><td>16,767</td><td>16,024</td><td>14,076</td><td>15,195</td></tr><tr><td> Total Steam Delivered to CECONY Customers</td><td>23,017</td><td>23,030</td><td>22,322</td><td>19,741</td><td>21,923</td></tr><tr><td> Steam Sold ($ in millions)</td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>General</td><td>$28</td><td>$25</td><td>$28</td><td>$25</td><td>$31</td></tr><tr><td>Apartment house</td><td>165</td><td>158</td><td>175</td><td>158</td><td>187</td></tr><tr><td>Annual power</td><td>446</td><td>457</td><td>487</td><td>429</td><td>491</td></tr><tr><td>Other operating revenues</td><td>22</td><td>16</td><td>-7</td><td>-16</td><td>-26</td></tr><tr><td> Total Steam Delivered to CECONY Customers</td><td>$661</td><td>$656</td><td>$683</td><td>$596</td><td>$683</td></tr><tr><td> Average Revenue per Mlb Sold</td><td>$27.76</td><td>$27.79</td><td>$30.91</td><td>$31.00</td><td>$32.34</td></tr></table>

Question: What's the sum of 2016 to 2020 of Foreign, and Apartment house of Year Ended December 31, 2011 ?
Answer: 11288.0