Commercial airplanes deliveries as of December 31 were as follows:
## Table 0 ##
(1) Includes intercompany deliveries of nine aircraft in 2012, seven in 2011 and five in 2010.
(2) Includes three aircraft accounted for as revenues by BCA and as operating leases in consolidation.
Earnings From Operations Earnings from operations for 2012 increased by $1,216 million compared with 2011.
This was primarily due to higher new airplane deliveries, which drove an increase in earnings of $1,292 million, and lower research and development expense of $666 million primarily due to lower spending on the 747-8 and 787-8 programs.
These increases were partially offset by lower earnings of $742 million driven by higher fleet support costs, increased operating costs associated with business growth, other period costs and decreased earnings from commercial aviation services.
The decrease in operating margins from 9.7% in 2011 to 9.6% in 2012 was primarily due to the dilutive effect of the 787 and 747-8 deliveries.
Earnings from operations for 2011 increased by $489 million compared with 2010.
This increase reflects earnings of $376 million from higher revenues on new airplane deliveries, $180 million of higher earnings due to commercial aviation services volume and margins and $261 million of lower research and development expense, partially offset by increases of $328 million reflecting higher fleet support costs and other costs associated with business growth.
Backlog Firm backlog represents orders for products and services where no contingencies remain before we and the customer are required to perform.
Backlog does not include prospective orders where customer controlled contingencies remain, such as the customers receiving approval from their Board of Directors, shareholders or government and completing financing arrangements.
All such contingencies must be satisfied or have expired prior to recording a new firm order even if satisfying such conditions is highly certain.
Firm orders exclude options.
A number of our customers may have contractual remedies that may be implicated by program delays.
We continue to address customer claims and requests for other contractual relief as they arise.
However, once orders are included in firm backlog, orders remain in backlog until canceled or fulfilled, although the value of orders is adjusted as changes to price and schedule are agreed to with customers.
The increase in contractual backlog during 2012 was due to orders in excess of deliveries, partially reduced by cancellations of orders and changes in projected revenue escalation.
The decrease in unobligated backlog in 2012 was due to incremental funding of the existing multi-year contract for Commercial Airplanes’ share of the USAF contract for the KC-46A Tanker.
The increase in contractual backlog during 2011 was due to orders in excess of deliveries and changes in projected revenue escalation, partially reduced by cancellations of orders.
The increase in unobligated backlog in 2011 represents Commercial Airplanes’ share of the USAF contract for the KC-46A Tanker.
Backlog Total backlog is comprised of contractual backlog, which represents work we are on contract to perform for which we have received funding, and unobligated backlog, which represents work we are on contract to perform for which funding has not yet been authorized and appropriated.
BDS total backlog increased by 19% in 2012, from $60,041 million to $71,475 million, primarily due to F-15 and C-17 orders and the contract award for the Space Launch System program received in 2012.
For further details on the changes between periods, refer to the discussions of the individual segments below.
Additional Considerations Our BDS business includes a variety of development programs which have complex design and technical challenges.
Many of these programs have cost-type contracting arrangements.
In these cases, the associated financial risks are primarily in reduced fees, lower profit rates or program cancellation if cost, schedule or technical performance issues arise.
Examples of these programs include Ground-based Midcourse Defense (GMD), Proprietary and Space Launch Systems programs.
Some of our development programs are contracted on a fixed-price basis.
Many of these programs have highly complex designs.
As technical or quality issues arise during development, we may experience schedule delays and cost impacts, which could increase our estimated cost to perform the work or reduce our estimated price, either of which could result in a material charge or otherwise adversely affect our financial condition.
These programs are ongoing, and while we believe the cost and fee estimates incorporated in the financial statements are appropriate, the technical complexity of these programs creates financial risk as additional completion costs may become necessary or scheduled delivery dates could be extended, which could trigger termination provisions, the loss of satellite in-orbit incentive payments, or other financially significant exposure.
These programs have risk for reach-forward losses if our estimated costs exceed our estimated contract revenues.
Examples of significant fixed-price development programs include Airborne Early Warning and Control (AEW&C), Family of Advanced Beyond Line-of-Sight Terminals (FAB-T), India P-8I, Saudi F-15, USAF KC-46A Tanker, and commercial and military satellites.
Boeing Military Aircraft Operating Results (Dollars in millions)
## Table 1 ##
Revenues BMA revenues increased by 10% in 2012 compared with 2011.
The increase of $1,437 million in 2012 was primarily due to higher deliveries on the P-8A and Apache programs of $1,050 million and higher milestone revenue of $426 million on the KC-46A Tanker program.
In addition, F-15 program revenues were $450 million higher reflecting initial revenues on the contract for the Kingdom of Saudi Arabia partially offset by lower F-15 deliveries.
These increases were partially offset by decreases of $723 million related to fewer deliveries of C-17 aircraft in 2012 and the conclusion of the KC-767 International Tanker program in 2011.
Liquidity and Capital Resources Cash Flow Summary (Dollars in millions)
## Table 2 ##
Operating Activities Net cash provided by operating activities was $7.5 billion during 2012, an increase of $3.5 billion compared with 2011 primarily due to lower inventory growth in 2012, which was partially offset by $1.6 billion of contributions to our pension plans in 2012 compared with $0.5 billion in 2011 and $35 million in 2010.
Our investment in gross inventories increased by $6.2 billion in 2012, and by $9.8 billion in 2011, driven by higher investments in commercial airplane program inventory, primarily 787 inventory.
Advances and progress billings increased to $41.6 billion at December 31, 2012 compared with $39.8 billion at December 31, 2011 and $34.7 billion at December 31, 2010.
Investing Activities Cash used by investing activities totaled $3.8 billion during 2012 compared with $2.4 billion provided during 2011, largely due to higher contributions to investments in time deposits.
Net contributions to investments were $2 billion in 2012 compared with net proceeds from investments of $4 billion in 2011.
In 2012, capital expenditures totaled $1.7 billion, consistent with the prior year.
We expect capital expenditures to be higher in 2013 due to continued investment to support growth.
Financing Activities Cash used by financing activities was $3.5 billion during 2012, an increase of $1.8 billion compared with 2011 as a result of higher debt repayments of $1.1 billion and lower new borrowings of $0.7 billion.
In 2012, we repaid $2.1 billion of debt, including repayments of $0.9 billion of debt held at BCC.
At December 31, 2012 and 2011, the recorded balance of debt was $10.4 billion and $12.4 billion, of which $1.4 billion and $2.4 billion were classified as short-term.
This includes $2.5 billion and $3.4 billion of debt recorded at BCC, of which $0.6 billion and $0.9 billion were classified as short-term.
In 2012 and 2011, we had 1,007,706 and 350,778 shares transferred to us from employees for tax withholding and did not repurchase any shares through our open market share repurchase program.
In December 2012, we announced the resumption of this program with repurchases expected to total between $1.5 and $2 billion in 2013.
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 program that continues to serve as a significant potential source of short-term liquidity.
Throughout 2012 and at December 31, 2012, we had no commercial paper borrowings outstanding.
Currently, we have $4.6
($125 million) and higher maintenance outage costs ($18 million).
Additionally, operating profits in 2012 include costs of $184 million associated with the acquisition and integration of Temple-Inland, mill divestiture costs of $91 million, costs associated with the restructuring of our European Packaging business of $17 million and a $3 million gain for other items, while operating costs in 2011 included costs associated with signing an agreement to acquire Temple-Inland of $20 million and a gain of $7 million for other items.
## Table 3 ##
North American Industrial Packaging net sales were $11.6 billion in 2012 compared with $8.6 billion in 2011 and $8.4 billion in 2010.
Operating profits in 2012 were $1.0 billion ($1.3 billion excluding costs associated with the acquisition and integration of Temple-Inland and mill divestiture costs) compared with $1.1 billion (both including and excluding costs associated with signing an agreement to acquire Temple-Inland) in 2011 and $763 million ($776 million excluding facility closure costs) in 2010.
Sales volumes for the legacy business were about flat in 2012 compared with 2011.
Average sales price was lower mainly due to export containerboard sales prices which bottomed out in the first quarter but climbed steadily the rest of the year.
Input costs were lower for recycled fiber, wood and natural gas, but higher for starch.
Freight costs also increased.
Planned maintenance downtime costs were higher than in 2011.
Operating costs were higher largely due to routine inventory valuation adjustments Operating profits in 2012 benefited from $235 million of Temple-Inland synergies.
Market-related downtime in 2012 was about 570,000 tons compared with about 380,000 tons in 2011.
Operating profits in 2012 included $184 million of costs associated with the acquisition and integration of Temple-Inland and $91 million of costs associated with the divestiture of three containerboard mills.
Operating profits in 2011 included charges of $20 million for costs associated with the signing of the agreement to acquire TempleInland.
Looking ahead to 2013, sales volumes in the first quarter compared with the fourth quarter of 2012 are expected to increase slightly for boxes due to a higher number of shipping days.
Average sales price realizations are expected to reflect the pass-through to box customers of a containerboard price increase implemented in 2012.
Input costs are expected to be higher for recycled fiber, wood and starch.
Planned maintenance downtime costs are expected to be about $26 million higher with outages scheduled at eight mills compared with six mills in the 2012 fourth quarter.
Manufacturing operating costs are expected to be lower.
European Industrial Packaging net sales were $1.0 billion in 2012 compared with $1.1 billion in 2011 and $990 million in 2010.
Operating profits in 2012 were $53 million ($72 million excluding restructuring costs) compared with $66 million ($61 million excluding a gain for a bargain purchase price adjustment on an acquisition by our joint venture in Turkey and costs associated with the closure of our Etienne mill in France in 2009) in 2011 and $70 million ($73 million before closure costs for our Etienne mill) in 2010.
Sales volumes in 2012 were lower than in 2011 reflecting decreased demand for packaging in the industrial market due to a weaker overall economic environment in southern Europe.
Demand for packaging in the agricultural markets was about flat yearover-year.
Average sales margins increased due to sales price increases implemented during 2011 and 2012 and lower board costs.
Other input costs were higher, primarily for energy and distribution.
Operating profits in 2012 included a net gain of $10 million for an insurance settlement, partially offset by additional operating costs, related to the earthquakes in Northern Italy in May which affected our San Felice box plant.
Entering the first quarter of 2013, sales volumes are expected to be stable reflecting a seasonal decrease in market demand in agricultural markets offset by an increase in industrial markets.
Average sales margins are expected to improve due to lower input costs for containerboard.
Other input costs should be about flat.
Operating costs are expected to be higher reflecting the absence of the earthquake insurance settlement that was received in the 2012 fourth quarter.
Asian Industrial Packaging net sales and operating profits include the results of SCA Packaging since the acquisition on June 30, 2010, including the impact of incremental integration costs.
Net sales for the packaging operations were $400 million in 2012 compared with $410 million in 2011 and $255 million in 2010.
Operating profits for the packaging operations were $2 million in 2012 compared with $2 million in 2011 and a loss of $7 million (a loss of $4 million excluding facility closure costs) in 2010.
Operating profits were favorably impacted by higher average sales margins in 2012 compared with 2011, but this benefit was offset by lower sales volumes and higher raw material costs and operating costs.
Looking ahead to the first quarter of 2013, sales volumes and average sales margins are expected to decrease due to seasonality.
Net sales for the distribution operations were $260 million in 2012 compared with $285 million in 2011 and $240 million in 2010.
Operating profits were $3 million in 2012 compared with $3 million in 2011 and about breakeven in 2010.

Tables referenced above, in order (Table 0 first):
<table><tr><td></td><td>737</td><td></td><td>747</td><td>767</td><td>777</td><td>787</td><td></td><td>Total</td></tr><tr><td>2012</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Cumulative deliveries</td><td>4,293</td><td></td><td>1,458</td><td>1,040</td><td>1,066</td><td>49</td><td></td><td></td></tr><tr><td>Deliveries</td><td>415</td><td><sup>-1</sup></td><td>31</td><td>26</td><td>83</td><td>46</td><td><sup>-2</sup></td><td>601</td></tr><tr><td>2011</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Cumulative deliveries</td><td>3,878</td><td></td><td>1,427</td><td>1,014</td><td>983</td><td>3</td><td></td><td></td></tr><tr><td>Deliveries</td><td>372</td><td><sup>-1</sup></td><td>9</td><td>20</td><td>73</td><td>3</td><td></td><td>477</td></tr><tr><td>2010</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Cumulative deliveries</td><td>3,506</td><td></td><td>1,418</td><td>994</td><td>910</td><td></td><td></td><td></td></tr><tr><td>Deliveries</td><td>376</td><td><sup>-1</sup></td><td></td><td>12</td><td>74</td><td></td><td></td><td>462</td></tr></table>
<table><tr><td>Years ended December 31,</td><td>2012</td><td>2011</td><td>2010</td></tr><tr><td>Revenues</td><td>$16,384</td><td>$14,947</td><td>$14,238</td></tr><tr><td>% of total company revenues</td><td>20%</td><td>22%</td><td>22%</td></tr><tr><td>Earnings from operations</td><td>$1,581</td><td>$1,526</td><td>$1,250</td></tr><tr><td>Operating margins</td><td>9.6%</td><td>10.2%</td><td>8.8%</td></tr><tr><td>Contractual backlog</td><td>$29,674</td><td>$24,085</td><td>$25,094</td></tr><tr><td>Unobligated backlog</td><td>$9,286</td><td>$7,155</td><td>$8,297</td></tr></table>
<table><tr><td>Years ended December 31,</td><td>2012</td><td>2011</td><td>2010</td></tr><tr><td>Net earnings</td><td>$3,900</td><td>$4,018</td><td>$3,307</td></tr><tr><td>Non-cash items</td><td>2,728</td><td>2,140</td><td>2,679</td></tr><tr><td>Changes in working capital</td><td>880</td><td>-2,135</td><td>-3,034</td></tr><tr><td>Net cash provided by operating activities</td><td>7,508</td><td>4,023</td><td>2,952</td></tr><tr><td>Net cash (used)/provided by investing activities</td><td>-3,757</td><td>2,369</td><td>-4,831</td></tr><tr><td>Net cash used by financing activities</td><td>-3,477</td><td>-1,700</td><td>-1,962</td></tr><tr><td>Effect of exchange rate changes on cash and cash equivalents</td><td>18</td><td>-2</td><td>-15</td></tr><tr><td>Net increase/(decrease) in cash and cash equivalents</td><td>292</td><td>4,690</td><td>-3,856</td></tr><tr><td>Cash and cash equivalents at beginning of year</td><td>10,049</td><td>5,359</td><td>9,215</td></tr><tr><td>Cash and cash equivalents at end of period</td><td>$10,341</td><td>$10,049</td><td>$5,359</td></tr></table>
<table><tr><td>In millions</td><td>2012</td><td>2011</td><td>2010</td></tr><tr><td>Sales</td><td>$13,280</td><td>$10,430</td><td>$9,840</td></tr><tr><td>Operating Profit</td><td>1,066</td><td>1,147</td><td>826</td></tr></table>

Question: What's the average of Unobligated backlog of 2011, and Cash and cash equivalents at beginning of year of 2011 ?
Answer: 6257
Reasoning program: add(7155.0,5359.0), divide(#0,const_2)