Item 7.
Management’s Discussion and Analysis of Financial Condition and Results of Operations Overview U. S.  economic growth, retail sales and industrial production continued at a moderate pace in 2014, which resulted in growth in the small package delivery market.
Continued strong growth in e-commerce and omni-channel retail sales has driven package volume increases in both commercial and residential products.
Given these trends, overall volume growth was strong during the year, and products most aligned with business-to-consumer and retail industry shipments experienced the fastest growth.
Economic conditions in Europe have deteriorated somewhat, as solid growth in the United Kingdom is being offset by slower growth in Germany and general economic weakness in France and Italy.
Economic growth in Asia has continued, though growth in China has moderated.
The uneven nature of economic growth worldwide, combined with a trend towards more intra-regional trade, has led to shifting trade patterns and resulted in overcapacity in certain trade lanes.
These factors have created an environment in which customers are more likely to trade-down from premium express products to standard delivery products in both Europe and Asia.
As a result of these circumstances, we have adjusted our air capacity and cost structure in our transportation network to better match the prevailing volume mix levels.
Our broad portfolio of product offerings and the flexibilities inherent in our transportation network have helped us adapt to these changing trends.
While the worldwide economic environment has remained challenging in 2014, we have continued to undertake several initiatives in the U. S.  and internationally to (1) improve the flexibility and capacity in our delivery network; (2) improve yield management; and (3) increase operational efficiency and contain costs across all segments.
Most notably, the continued deployment of technology improvements (including several facility automation projects and the accelerated deployment of our On Road Integrated Optimization and Navigation system - "ORION") should increase our network capacity, and improve operational efficiency, flexibility and reliability.
Additionally, we have continued to adjust our transportation network and utilize new or expanded operating facilities to improve time-in-transit for shipments in each region.
Our consolidated results are presented in the table below:
||Year Ended December 31,|% Change|
||2014|2013|2012|2014 / 2013|2013 / 2012|
|Revenue (in millions)|$58,232|$55,438|$54,127|5.0%|2.4%|
|Operating Expenses (in millions)|53,264|48,404|52,784|10.0%|-8.3%|
|Operating Profit (in millions)|$4,968|$7,034|$1,343|-29.4%|N/A|
|Operating Margin|8.5%|12.7%|2.5%|||
|Average Daily Package Volume (in thousands)|18,016|16,938|16,295|6.4%|3.9%|
|Average Revenue Per Piece|$10.58|$10.76|$10.82|-1.7%|-0.6%|
|Net Income (in millions)|$3,032|$4,372|$807|-30.6%|N/A|
|Basic Earnings Per Share|$3.31|$4.65|$0.84|-28.8%|N/A|
|Diluted Earnings Per Share|$3.28|$4.61|$0.83|-28.9%|N/A|

UNITED PARCEL SERVICE, INC.  AND SUBSIDIARIES MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS 30 Revenue The change in overall revenue was impacted by the following factors for the years ended December 31, 2014 and 2013, compared with the corresponding prior year periods:
||Volume|Rates /Product Mix|FuelSurcharge|TotalRevenueChange|
|Revenue Change Drivers:|||||
|2014 / 2013|6.8%|-1.6%|—%|5.2%|
|2013 / 2012|3.7%|0.5%|-0.5%|3.7%|

Volume 2014 compared to 2013 Our total volume increased in 2014, largely due to continued solid growth in e-commerce and overall retail sales.
Business-to-consumer shipments, which represent more than 45% of total U. S.  Domestic Package volume, grew 12% for the year and drove increases in both air and ground shipments.
UPS SurePost volume increased more than 45% in 2014, and accounted for approximately half of the overall volume growth for the segment.
Business-to-business volume grew 3% in 2014, largely due to increased volume from the retail industry, including the use of our solutions for omni-channel (including ship-from-store and ship-to-store models) and returns shipping; additionally, business-to-business volume was positively impacted by growth in shipments from the industrial, automotive and government sectors.
Among our air products, volume increased in 2014 for both our Next Day Air and deferred services.
Solid air volume growth continued for those products most aligned with business-to-consumer shipping, particularly our residential Second Day Air package product.
Our business-to-business air volume increased slightly as well, largely due to growth in the retail and industrial sectors.
This growth was slightly offset by a decline in air letter volume, which was negatively impacted by some competitive losses and slowing growth in the financial services industry.
The growth in premium and deferred air volume continues to be impacted by economic conditions and changes in our customers' supply chain networks; the combination of these factors influences their sensitivity towards the price and speed of shipments, and therefore favoring the use of our deferred air services.
The increase in ground volume in 2014 was driven by our SurePost service offering, which had a volume increase of more than 45% for the year; additionally, we experienced moderate volume growth in our traditional residential and commercial ground services.
Demand for SurePost and our traditional residential products continues to be driven by businessto-consumer shipping activity from e-commerce retailers and other large customers.
The growth in business-to-business ground volume was largely due to growth in omni-channel retail volume, the increased use of our returns service offerings, and the growth in shipments from the industrial sector.2013 compared to 2012 Our overall volume increased in 2013 compared with 2012, largely due to continued solid growth in e-commerce and overall retail sales; however, the increase in volume was hindered by slow overall U. S.  economic and industrial production growth.
Business-to-consumer shipments, which represent over 40% of total U. S.  Domestic Package volume, grew approximately 8% for the year and drove increases in both air and ground shipments.
Growth accelerated during our peak holiday shipping season, as business-to-consumer volume grew over 11% in the fourth quarter of 2013, and business-toconsumer shipments exceeded 50% of total U. S.  Domestic Package volume for the first time.
Business-to-business volume increased slightly in 2013, largely due to increased shipping activity by the retail industry; however, business-to-business volume was negatively impacted by slowing industrial production.
UNITED PARCEL SERVICE, INC.  AND SUBSIDIARIES MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS 49 Issuances of debt in 2014 and 2013 consisted primarily of longer-maturity commercial paper.
Issuances of debt in 2012 consisted primarily of senior fixed rate note offerings totaling $1.75 billion.
Repayments of debt in 2014 and 2013 consisted primarily of the maturity of our $1.0 and $1.75 billion senior fixed rate notes that matured in April 2014 and January 2013, respectively.
The remaining repayments of debt during the 2012 through 2014 time period included paydowns of commercial paper and scheduled principal payments on our capitalized lease obligations.
We consider the overall fixed and floating interest rate mix of our portfolio and the related overall cost of borrowing when planning for future issuances and non-scheduled repayments of debt.
We had $772 million of commercial paper outstanding at December 31, 2014, and no commercial paper outstanding at December 31, 2013 and 2012.
The amount of commercial paper outstanding fluctuates throughout each year based on daily liquidity needs.
The average commercial paper balance was $1.356 billion and the average interest rate paid was 0.10% in 2014 ($1.013 billion and 0.07% in 2013, and $962 million and 0.07% in 2012, respectively).
The variation in cash received from common stock issuances to employees was primarily due to level of stock option exercises in the 2012 through 2014 period.
The cash outflows in other financing activities were impacted by several factors.
Cash inflows (outflows) from the premium payments and settlements of capped call options for the purchase of UPS class B shares were $(47), $(93) and $206 million for 2014, 2013 and 2012, respectively.
Cash outflows related to the repurchase of shares to satisfy tax withholding obligations on vested employee stock awards were $224, $253 and $234 million for 2014, 2013 and 2012, respectively.
In 2013, we paid $70 million to purchase the noncontrolling interest in a joint venture that operates in the Middle East, Turkey and portions of the Central Asia region.
In 2012, we settled several interest rate derivatives that were designated as hedges of the senior fixed-rate debt offerings that year, which resulted in a cash outflow of $70 million.
Sources of Credit See note 7 to the audited consolidated financial statements for a discussion of our available credit and debt covenants.
Guarantees and Other Off-Balance Sheet Arrangements We do not have guarantees or other off-balance sheet financing arrangements, including variable interest entities, which we believe could have a material impact on financial condition or liquidity.
Contractual Commitments We have contractual obligations and commitments in the form of capital leases, operating leases, debt obligations, purchase commitments, and certain other liabilities.
We intend to satisfy these obligations through the use of cash flow from operations.
The following table summarizes the expected cash outflow to satisfy our contractual obligations and commitments as of December 31, 2014 (in millions):
|Commitment Type|2015|2016|2017|2018|2019|After 2019|Total|
|Capital Leases|$75|$74|$67|$62|$59|$435|$772|
|Operating Leases|323|257|210|150|90|274|1,304|
|Debt Principal|876|8|377|752|1,000|7,068|10,081|
|Debt Interest|295|293|293|282|260|4,259|5,682|
|Purchase Commitments|269|195|71|19|8|26|588|
|Pension Fundings|1,030|1,161|344|347|400|488|3,770|
|Other Liabilities|43|23|10|5|—|—|81|
|Total|$2,911|$2,011|$1,372|$1,617|$1,817|$12,550|$22,278|


Question: What was the average of the Operating Expenses in the years where Revenue is positive? (in million)

Python solution:
def solution():
    # Define variables name and value
    operating_expenses_2014 = 53264
    operating_expenses_2013 = 48404
    operating_expenses_2012 = 52784
    const_3 = 3
    
    # Do math calculation to get the answer
    answer = (operating_expenses_2014 + operating_expenses_2013 + operating_expenses_2012) / const_3
    
    return answer

Answer: 51484