Revenues N&SS revenues decreased 1% in 2008 and 2% in 2007.
The decrease of $137 million in 2008 is primarily due to decreased revenues in FCS, Proprietary and satellite programs partially offset by increased revenues in the SBInet program.
The decrease of $292 million in 2007 was primarily due to the exclusion of government Delta volume, now a component of our equity investment in ULA and lower FCS volume, partially offset by increased volume on SBInet and several satellite programs.
Delta launch and new-build satellite deliveries were as follows:
## Table 0 ##
Delta government launches are excluded from our deliveries after December 1, 2006 due to the formation of ULA.
Operating Earnings N&SS operating earnings increased by $171 million in 2008 was primarily due to increased earnings from our investment in ULA.
The decrease in 2007 was due to lower earnings on FCS and several satellite programs.
These decreases were partially offset by higher award fees on GMD and a $44 million gain on sale of a property in Anaheim.
N&SS operating earnings include equity earnings of $73 million, $85 million and $71 million from the United Space Alliance joint venture in 2008, 2007, and 2006, respectively and equity earnings of $105 million, a loss of $11 million and equity earnings of $5 million from the ULA joint venture in 2008, 2007 and 2006, respectively.
The ULA equity earnings and loss amounts are net of the basis difference amortization.
Research and Development The N&SS research and development funding remains focused on the development of communications, command and control, computers, intelligence, surveillance and reconnaissance systems (C4ISR); communications and command and control (C3) capabilities that support a network-enabled architecture approach for our various government customers.
We are investing in communications capabilities to enable connectivity between existing air/ground platforms, increase communications availability and bandwidth through more robust space systems, and leverage innovative communications concepts.
Key programs in this area include JTRS, FCS, Global Positioning System, Tracking and Data Relay Satellite, Ares 1 Crew Launch Vehicle and GMD.
Investments were also made to support concepts that may lead to the development of next-generation space intelligence systems.
Along with increased funding to support these areas of architecture and network-enabled capabilities development, we also maintained our investment levels in global missile defense and advanced missile defense concepts and technologies.
Backlog N&SS total backlog decreased by 12% in 2008 compared with 2007 primarily due to revenues recognized on multi-year orders received in prior years on FCS, GMD and C3 programs, partially offset by an increase in the International Space Station program.
Total backlog decreased by 7% in 2007 compared with 2006 due to revenues recognized on FCS and Proprietary programs, partially offset by an increase in Space Exploration programs.
Additional Considerations Items which could have a future impact on N&SS operations include the following: United Launch Alliance On December 1, 2006, we completed the transaction with Lockheed Martin Corporation (Lockheed) to create a 50/50 joint venture named United Launch Alliance L. L. C.  (ULA).
ULA combines the production, engineering, test and launch operations associated with U. S.  government launches of Boeing Delta and Lockheed Atlas rockets.
In connection with the transaction,
billion of unused borrowing on revolving credit line agreements.
We anticipate that these credit lines will primarily serve as backup liquidity to support our general corporate borrowing needs.
Financing commitments totaled $18.1 billion and $15.9 billion as of December 31, 2012 and 2011.
We anticipate that we will not be required to fund a significant portion of our financing commitments as we continue to work with third party financiers to provide alternative financing to customers.
Historically, we have not been required to fund significant amounts of outstanding commitments.
However, there can be no assurances that we will not be required to fund greater amounts than historically required.
In the event we require additional funding to support strategic business opportunities, our commercial aircraft financing commitments, unfavorable resolution of litigation or other loss contingencies, or other business requirements, we expect to meet increased funding requirements by issuing commercial paper or term debt.
We believe our ability to access external capital resources should be sufficient to satisfy existing short-term and long-term commitments and plans, and also to provide adequate financial flexibility to take advantage of potential strategic business opportunities should they arise within the next year.
However, there can be no assurance of the cost or availability of future borrowings, if any, under our commercial paper program, in the debt markets or our credit facilities.
At December 31, 2012 and 2011, our pension plans were $19.7 billion and $16.6 billion underfunded as measured under GAAP.
On an ERISA basis our plans are more than 100% funded at December 31, 2012 with minimal required contributions in 2013.
We expect to make discretionary contributions to our plans of approximately $1.5 billion in 2013.
We may be required to make higher contributions to our pension plans in future years.
As of December 31, 2012, we were in compliance with the covenants for our debt and credit facilities.
The most restrictive covenants include a limitation on mortgage debt and sale and leaseback transactions as a percentage of consolidated net tangible assets (as defined in the credit agreements), and a limitation on consolidated debt as a percentage of total capital (as defined).
When considering debt covenants, we continue to have substantial borrowing capacity.
Contractual Obligations The following table summarizes our known obligations to make future payments pursuant to certain contracts as of December 31, 2012, and the estimated timing thereof.
## Table 1 ##
(1) Includes interest on variable rate debt calculated based on interest rates at December 31, 2012.
Variable rate debt was less than 1% of our total debt at December 31, 2012.
Industry Competitiveness The commercial jet airplane market and the airline industry remain extremely competitive.
Market liberalization in Europe, the Middle East and Asia is enabling low-cost airlines to continue gaining market share.
These airlines are increasing the pressure on airfares.
This results in continued cost pressures for all airlines and price pressure on our products.
Major productivity gains are essential to ensure a favorable market position at acceptable profit margins.
Continued access to global markets remains vital to our ability to fully realize our sales potential and longterm investment returns.
Approximately 91% of Commercial Airplanes’ total backlog, in dollar terms, is with non-U.
S.  airlines.
We face aggressive international competitors who are intent on increasing their market share.
They offer competitive products and have access to most of the same customers and suppliers.
With government support,Airbus has historically invested heavily to create a family of products to compete with ours.
Regional jet makers Embraer and Bombardier continue to develop and market larger and increasingly more capable airplanes, including Embraer’s E-195 in the regional jet market and Bombardier’s C Series in the 100-150 seat transcontinental market.
Additionally, other competitors from Russia, China and Japan are developing commercial jet aircraft.
Some of these competitors have historically enjoyed access to governmentprovided financial support, including “launch aid,” which greatly reduces the cost and commercial risks associated with airplane development activities.
This has enabled the development of airplanes without commercial viability; others to be brought to market more quickly than otherwise possible; and many offered for sale below market-based prices.
Many competitors have continued to make improvements in efficiency, which may result in funding product development, gaining market share and improving earnings.
This market environment has resulted in intense pressures on pricing and other competitive factors, and we expect these pressures to continue or intensify in the coming years.
We are focused on improving our products and services and continuing our cost-reduction efforts, which enhances our ability to compete.
We are also focused on taking actions to ensure that Boeing is not harmed by unfair subsidization of competitors.
Results of Operations
## Table 2 ##
Revenues Commercial Airplanes revenues decreased by $1,283 million or 2% in 2017 compared with 2016 due to delivery mix, with fewer twin aisle deliveries more than offsetting the impact of higher single aisle deliveries.
Commercial Airplanes revenues decreased by $1,387 million or 2% in 2016 compared with 2015 primarily due to fewer deliveries.
Through February 25, 2016, we repurchased approximately $415.0 million of shares of our common stock, which includes the $250.0 million of shares that we repurchased from certain selling stockholders on February 10, 2016.
In order to achieve operational synergies, we expect cash outlays related to our integration plans to be approximately $290.0 million in 2016.
These cash outlays are necessary to achieve our integration goals of net annual pre-tax operating profit synergies of $350.0 million by the end of the third year post-Closing Date.
Also as discussed in Note 20 to our consolidated financial statements, as of December 31, 2015, a short-term liability of $50.0 million and long-term liability of $264.6 million related to Durom Cup product liability claims was recorded on our consolidated balance sheet.
We expect to continue paying these claims over the next few years.
We expect to be reimbursed a portion of these payments for product liability claims from insurance carriers.
As of December 31, 2015, we have received a portion of the insurance proceeds we estimate we will recover.
We have a long-term receivable of $95.3 million remaining for future expected reimbursements from our insurance carriers.
We also had a short-term liability of $33.4 million related to Biomet metal-on-metal hip implant claims.
At December 31, 2015, we had ten tranches of senior notes outstanding as follows (dollars in millions):

<table><tr><td>Years ended December 31,</td><td> 2008</td><td>2007</td><td>2006</td></tr><tr><td>Delta II Commercial</td><td> 2</td><td>3</td><td></td></tr><tr><td>Delta II Government</td><td></td><td></td><td>2</td></tr><tr><td>Delta IV Government</td><td></td><td></td><td>3</td></tr><tr><td>Satellites</td><td> 1</td><td>4</td><td>4</td></tr></table>
<table><tr><td>(Dollars in millions)</td><td>Total</td><td>Lessthan 1year</td><td>1-3years</td><td>3-5years</td><td>After 5years</td></tr><tr><td>Long-term debt (including current portion)</td><td>$10,251</td><td>$1,340</td><td>$2,147</td><td>$1,095</td><td>$5,669</td></tr><tr><td>Interest on debt<sup>-1</sup></td><td>6,177</td><td>510</td><td>864</td><td>749</td><td>4,054</td></tr><tr><td>Pension and other postretirement cash requirements</td><td>25,558</td><td>579</td><td>1,244</td><td>7,025</td><td>16,710</td></tr><tr><td>Capital lease obligations</td><td>184</td><td>102</td><td>78</td><td>4</td><td></td></tr><tr><td>Operating lease obligations</td><td>1,405</td><td>218</td><td>334</td><td>209</td><td>644</td></tr><tr><td>Purchase obligations not recorded on the Consolidated Statements of Financial Position</td><td>118,002</td><td>44,472</td><td>41,838</td><td>18,956</td><td>12,736</td></tr><tr><td>Purchase obligations recorded on the Consolidated Statements of Financial Position</td><td>15,981</td><td>14,664</td><td>1,307</td><td>1</td><td>9</td></tr><tr><td>Total contractual obligations</td><td>$177,558</td><td>$61,885</td><td>$47,812</td><td>$28,039</td><td>$39,822</td></tr></table>
<table><tr><td>Years ended December 31,</td><td>2017</td><td>2016</td><td>2015</td></tr><tr><td>Revenues</td><td>$56,729</td><td>$58,012</td><td>$59,399</td></tr><tr><td>% of total company revenues</td><td>61%</td><td>61%</td><td>62%</td></tr><tr><td>Earnings from operations</td><td>$5,432</td><td>$1,995</td><td>$4,284</td></tr><tr><td>Operating margins</td><td>9.6%</td><td>3.4%</td><td>7.2%</td></tr><tr><td>Research and development</td><td>$2,247</td><td>$3,706</td><td>$2,311</td></tr></table>

Question: What is the sum amount of Capital lease obligations in the years with the lowest amount of Operating lease obligations? (in dollars in millions)
Answer: 4