Accounting Quantity The accounting quantity is our estimate of the quantity of airplanes that will be produced for delivery under existing and anticipated contracts.
The determination of the accounting quantity is limited by the ability to make reasonably dependable estimates of the revenue and cost of existing and anticipated contracts.
It is a key determinant of the gross margins we recognize on sales of individual airplanes throughout a program’s life.
Estimation of each program’s accounting quantity takes into account several factors that are indicative of the demand for that program, including firm orders, letters of intent from prospective customers and market studies.
We review our program accounting quantities quarterly.
The accounting quantity for each program may include units that have been delivered, undelivered units under contract, and units anticipated to be under contract in the reasonable future (anticipated orders).
In developing total program estimates, all of these items within the accounting quantity must be considered.
The following table provides details of the accounting quantities and firm orders by program as of December 31.
Cumulative firm orders represent the cumulative number of commercial jet aircraft deliveries plus undelivered firm orders.
## Table 0 ##
* The initial accounting quantity for the 787 program was established in the third quarter of 2011.737 Program The accounting quantity for the 737 program increased by 400 units during 2012 due to the program’s normal progress of obtaining additional orders and delivering airplanes.
As planned, production increased from 31.5 to 35 airplanes per month during 2012.
We continue to expect to increase production from 35 to 38 airplanes per month beginning in 2013 and a further increase to 42 airplanes per month beginning in 2014.
The majority of the 737 orders during 2012 related to the 737 MAX, the new engine variant of the 737.
The accounting quantity for the 737 program includes NG and MAX units.
First delivery of the 737 MAX is expected in 2017.747 Program The accounting quantity for the 747 program increased by 25 units in 2012, reflecting the normal process of estimating planned production under existing and anticipated contracts.
We continue to incorporate changes identified during flight testing into previously completed airplanes.
First delivery of the 747-8 Intercontinental occurred in February 2012.
The production rate increased from 1.5 to 2 airplanes per month in May 2012.
Ongoing weakness in the air cargo market and lower-than-expected demand for large commercial passenger aircraft have resulted in pricing pressures and fewer orders than anticipated in 2012.
We have a number of unsold Freighter and Intercontinental production positions beyond 2013.
If we are unable to obtain orders for multiple Freighter aircraft in 2013 consistent with our near-term production plans, we may be required to take actions including
Liquidity and Capital Resources Cash Flow Summary
## Table 1 ##
Operating Activities Net cash provided by operating activities was $13.3 billion during 2017, compared with $10.5 billion during 2016 and $9.4 billion in 2015.
The increase of $2.8 billion in 2017 was primarily driven by higher advances more than offsetting inventory increases.
The increase of $1.1 billion in 2016 was primarily due to lower expenditures on commercial airplane program inventory, primarily 787.
Advances and progress billings increased by $4.6 billion in 2017, decreased by $1.9 billion in 2016 and increased by $0.4 billion in 2015.
During 2017, our discretionary contributions to our pension plans included 14.4 million shares of our common stock with an aggregate value of $3.5 billion and $0.5 billion in cash.
Discretionary contributions to our pension plans were insignificant in 2016 and 2015.
Investing Activities Cash used by investing activities during 2017, 2016 and 2015 was $2.1 billion, $3.4 billion and $1.8 billion.
Capital expenditures totaled $1.7 billion in 2017, down from $2.6 billion in 2016 and $2.5 billion in 2015.
We expect capital expenditures in 2018 to be higher than 2017.
Net proceeds from investments was insignificant in 2017.
Net contributions to investments were $0.5 billion in 2016 compared with net proceeds from investments of $0.6 billion in 2015.  Financing Activities Cash used by financing activities was $11.4 billion during 2017, an increase of $1.8 billion compared with 2016, primarily due to higher share repurchases and dividend payments.
During 2017, our net borrowings were $1.1 billion compared with minimal net repayments in 2016.
Cash used by financing activities was $9.6 billion during 2016, an increase of $1.7 billion compared with 2015, primarily due to lower net borrowings and higher dividend payments and share repurchases.
At December 31, 2017 and 2016 the recorded balance of debt was $11.1 billion and $10.0 billion of which $1.3 billion and $0.4 billion was classified as short-term.
At December 31, 2017 and 2016 this included $2.5 billion and $2.9 billion of debt attributable to BCC, of which $0.9 billion and $0.1 billion were classified as short-term.
During 2017 and 2016 we repurchased 46.1 million and 55.1 million shares totaling $9.2 billion and $7.0 billion through our open market share repurchase program.
In 2017 and 2016, we had 0.7 million shares transferred to us from employees for tax withholdings.
At December 31, 2017, the amount available under the share repurchase plan, announced on December 11, 2017, totaled $18 billion.
Capital Resources We have substantial borrowing capacity.
Any future borrowings may affect our credit ratings and are subject to various debt covenants as described below.
We have a commercial paper
production capacity, learning curve, additional change incorporation, achieving anticipated cost reductions, flight test and certification schedules, costs, schedule and demand for new airplanes and derivatives and status of customer claims, supplier assertions and other contractual negotiations.
While we believe the cost and revenue estimates incorporated in the consolidated financial statements are appropriate, the technical complexity of our airplane programs creates financial risk as additional completion costs may become necessary or scheduled delivery dates could be extended, which could trigger termination provisions, order cancellations or other financially significant exposure.
Defense, Space & Security Business Environment and Trends United States Government Defense Environment Overview The Bipartisan Budget Act of 2018, passed in February 2018, raised the 2011 Budget Control Act spending caps for fiscal years 2018 and 2019 (FY18 and FY19).
The consolidated spending bills signed into law in September 2018 provide defense funding for FY19, in compliance with the revised caps.
These bills also provide FY19 appropriations for most of the federal government.
Full year funding for the departments and agencies not covered by enacted FY19 appropriations, including the National Aeronautics and Space Administration (NASA) and Federal Aviation Administration (FAA), remains uncertain.
The unfunded departments and agencies affected by the partial government shutdown (December 22, 2018 through January 25, 2019) are now covered by a Continuing Resolution that extends funding at FY18 levels through February 15, 2019.
Congress and the President must agree to FY19 appropriations or an additional Continuing Resolution to fund affected departments and agencies beyond the February 15 deadline in order to prevent a second partial government shutdown.
The impact of a partial government shutdown to the Company’s operations would increase as the shutdown continues.
There continues to be uncertainty with respect to future program-level appropriations for the U. S.  DoD and other government agencies, including NASA.
The 2011 Budget Control Act continues to mandate limits on U. S.  government discretionary spending for fiscal years 2020 and 2021 (FY20 and FY21).
The lower budget caps will take effect again in FY20 and FY21 unless Congress acts to raise the spending caps or to repeal or suspend the law.
As a result, continued budget uncertainty and the risk of future sequestration cuts remain.
Future budget cuts or investment priority changes could result in reductions, cancellations and/or delays of existing contracts or programs.
Any of these impacts could have a material effect on the results of the Company’s operations, financial position and/or cash flows.
Non-U.
S.  Defense Environment Overview The non-U.
S.  market continues to be driven by complex and evolving security challenges and the need to modernize aging equipment and inventories.
BDS expects that it will continue to have a wide range of opportunities across Asia, Europe and the Middle East given the diverse regional threats.
At the end of 2018, 30% of BDS backlog was attributable to non-U.
S.  customers.
Results of Operations
## Table 2 ##
SCHEDULE III Page 6 of 6 HOST HOTELS & RESORTS, INC. , AND SUBSIDIARIES HOST HOTELS & RESORTS, L. P. , AND SUBSIDIARIES REAL ESTATE AND ACCUMULATED DEPRECIATION December 31, 2017 (in millions) (B) The change in accumulated depreciation and amortization of real estate assets for the fiscal years ended December 31, 2017, 2016 and 2015 is as follows:

<table><tr><td></td><td colspan="5">Program</td></tr><tr><td></td><td>737</td><td>747</td><td>767</td><td>777</td><td>787</td></tr><tr><td>2012</td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Program accounting quantities</td><td>6,600</td><td>1,574</td><td>1,103</td><td>1,450</td><td>1,100</td></tr><tr><td>Undelivered units under firm orders</td><td>3,074</td><td>67</td><td>68</td><td>365</td><td>799</td></tr><tr><td>Cumulative firm orders</td><td>7,367</td><td>1,525</td><td>1,108</td><td>1,431</td><td>848</td></tr><tr><td>2011</td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Program accounting quantities</td><td>6,200</td><td>1,549</td><td>1,084</td><td>1,350</td><td>1,100</td></tr><tr><td>Undelivered units under firm orders</td><td>2,365</td><td>97</td><td>72</td><td>380</td><td>857</td></tr><tr><td>Cumulative firm orders</td><td>6,243</td><td>1,524</td><td>1,086</td><td>1,363</td><td>860</td></tr><tr><td>2010</td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Program accounting quantities</td><td>5,000</td><td>1,524</td><td>1,048</td><td>1,150</td><td>*</td></tr><tr><td>Undelivered units under firm orders</td><td>2,186</td><td>107</td><td>50</td><td>253</td><td>847</td></tr><tr><td>Cumulative firm orders</td><td>5,692</td><td>1,525</td><td>1,044</td><td>1,163</td><td>847</td></tr></table>
<table><tr><td>Years ended December 31,</td><td>2017</td><td>2016</td><td>2015</td></tr><tr><td>Net earnings</td><td>$8,197</td><td>$4,895</td><td>$5,176</td></tr><tr><td>Non-cash items</td><td>2,652</td><td>2,559</td><td>2,392</td></tr><tr><td>Changes in working capital</td><td>2,495</td><td>3,045</td><td>1,795</td></tr><tr><td>Net cash provided by operating activities</td><td>13,344</td><td>10,499</td><td>9,363</td></tr><tr><td>Net cash used by investing activities</td><td>-2,062</td><td>-3,380</td><td>-1,846</td></tr><tr><td>Net cash used by financing activities</td><td>-11,350</td><td>-9,587</td><td>-7,920</td></tr><tr><td>Effect of exchange rate changes on cash and cash equivalents</td><td>80</td><td>-33</td><td>-28</td></tr><tr><td>Net decrease in cash and cash equivalents</td><td>12</td><td>-2,501</td><td>-431</td></tr><tr><td>Cash and cash equivalents at beginning of year</td><td>8,801</td><td>11,302</td><td>11,733</td></tr><tr><td>Cash and cash equivalents at end of period</td><td>$8,813</td><td>$8,801</td><td>$11,302</td></tr></table>
<table><tr><td>Years ended December 31,</td><td>2018</td><td>2017</td><td>2016</td></tr><tr><td>Revenues</td><td>$23,195</td><td>$20,561</td><td>$20,180</td></tr><tr><td>% of total company revenues</td><td>23%</td><td>22%</td><td>22%</td></tr><tr><td>Earnings from operations</td><td>$1,594</td><td>$2,193</td><td>$1,678</td></tr><tr><td>Operating margins</td><td>6.9%</td><td>10.7%</td><td>8.3%</td></tr></table>

Question: What's the sum of Net cash used by financing activities of 2015, Program accounting quantities 2011 of Program.4, and Undelivered units under firm orders 2011 of Program ?
Answer: 11385