THE GOLDMAN SACHS GROUP, INC.  AND SUBSIDIARIES Management’s Discussion and Analysis Net revenues in Equities were $6.60 billion, 4% lower than 2016, primarily due to lower commissions and fees, reflecting a decline in our listed cash equity volumes in the U. S.  Market volumes in the U. S.  also declined.
In addition, net revenues in equities client execution were lower, reflecting lower net revenues in derivatives, partially offset by higher net revenues in cash products.
Net revenues in securities services were essentially unchanged.
Operating expenses were $9.69 billion for 2017, essentially unchanged compared with 2016, due to decreased compensation and benefits expenses, reflecting lower net revenues, largely offset by increased technology expenses, reflecting higher expenses related to cloud-based services and software depreciation, and increased consulting costs.
Pre-tax earnings were $2.21 billion in 2017, 54% lower than 2016.
Investing & Lending Investing & Lending includes our investing activities and the origination of loans, including our relationship lending activities, to provide financing to clients.
These investments and loans are typically longer-term in nature.
We make investments, some of which are consolidated, including through our Merchant Banking business and our Special Situations Group, in debt securities and loans, public and private equity securities, infrastructure and real estate entities.
Some of these investments are made indirectly through funds that we manage.
We also make unsecured loans through our digital platform, Marcus: by Goldman Sachs and secured loans through our digital platform, Goldman Sachs Private Bank Select.
The table below presents the operating results of our Investing & Lending segment.
## Table 0 ##
Operating Environment.
During 2018, our investments in private equities benefited from company-specific events, including sales, and strong corporate performance, while investments in public equities reflected losses, as global equity prices generally decreased.
Results for our investments in debt securities and loans reflected continued growth in loans receivables, resulting in higher net interest income.
If macroeconomic concerns negatively affect corporate performance or the origination of loans, or if global equity prices continue to decline, net revenues in Investing & Lending would likely be negatively impacted.
During 2017, generally higher global equity prices and tighter credit spreads contributed to a favorable environment for our equity and debt investments.
Results also reflected net gains from company-specific events, including sales, and corporate performance.2018 versus 2017.
Net revenues in Investing & Lending were $8.25 billion for 2018, 14% higher than 2017.
Net revenues in equity securities were $4.46 billion, 3% lower than 2017, reflecting net losses from investments in public equities (2018 included $183 million of net losses) compared with net gains in the prior year, partially offset by significantly higher net gains from investments in private equities (2018 included $4.64 billion of net gains), driven by company-specific events, including sales, and corporate performance.
For 2018, 60% of the net revenues in equity securities were generated from corporate investments and 40% were generated from real estate.
Net revenues in debt securities and loans were $3.80 billion, 43% higher than 2017, primarily driven by significantly higher net interest income.2018 included net interest income of approximately $2.70 billion compared with approximately $1.80 billion in 2017.
Provision for credit losses was $674 million for 2018, compared with $657 million for 2017, as the higher provision for credit losses primarily related to consumer loan growth in 2018 was partially offset by an impairment of approximately $130 million on a secured loan in 2017.
Operating expenses were $3.37 billion for 2018, 20% higher than 2017, primarily due to increased expenses related to consolidated investments and our digital lending and deposit platform, and increased compensation and benefits expenses, reflecting higher net revenues.
Pre-tax earnings were $4.21 billion in 2018, 11% higher than 2017.2017 versus 2016.
Net revenues in Investing & Lending were $7.24 billion for 2017, 70% higher than 2016.
Net revenues in equity securities were $4.58 billion, 78% higher than 2016, primarily reflecting a significant increase in net gains from private equities (2017 included $3.82 billion of net gains), which were positively impacted by company-specific events and corporate performance.
In addition, net gains from public equities (2017 included $762 million of net gains) were significantly higher, as global equity prices increased during the year.
For 2017, 64% of the net revenues in equity securities were generated from corporate investments and 36% were generated from real estate.
Net revenues in debt securities and loans were $2.66 billion, 57% higher than 2016, reflecting significantly higher net interest income (2017 included approximately $1.80 billion of net interest income).
In accordance with EITF 97-14, all fluctuations in market value of the deferred compensation liability have been reflected in other expense, net in the consolidated statements of operations.
We recognized deferred compensation income of $32 million in 2008 and deferred compensation expense of $33 million in 2007 and $16 million in 2006.
We also maintain an unfunded deferred compensation plan for the benefit of certain of our employees.
A deferred compensation liability of $36 million was outstanding at December 31, 2008 under the unfunded plan.
Note 13 – Stock-Based Compensation As discussed in Note 2—Summary of Significant Accounting Policies, effective January 1, 2006, we adopted the fair value recognition provisions for stock-based awards granted to employees.
SFAS 123(R) requires companies to recognize in the statement of operations the grant-date fair value of stock options and other stock-based compensation issued to employees.
We recognize the expense of all stock-based awards on a straight-line basis over the employee’s requisite service period (generally the vesting period of the award).
We recognized total stock-based compensation expense as follows:
## Table 1 ##
Stock Option and Restricted Stock Plans and Incentive Plan—Our stock option and restricted stock plans and incentive plan are described below.1992 Stock Option and Restricted Stock Plan Under the Noble Energy, Inc.  1992 Stock Option and Restricted Stock Plan, as amended (the 1992 Plan), the Compensation, Benefits and Stock Option Committee of the Board of Directors (the Committee) may grant stock options and award restricted stock to our officers or other employees and those of our subsidiaries.
During 2007, our stockholders approved an amendment to the 1992 Plan that increased the maximum number of shares of our common stock that may be issued from 18,500,000 to 22,000,000 shares.
At December 31, 2008, 10,469,623 shares of common stock were reserved for issuance, including 4,698,788 shares available for future grants and awards, under the 1992 Plan.1992 Plan Stock Options—Stock options are issued with an exercise price equal to the market price of our common stock on the date of grant, and are subject to such other terms and conditions as may be determined by the Committee.
Unless granted by the Committee for a shorter term, the options expire ten years from the grant date.
Option grants generally vest ratably over a three-year period.1992 Plan Restricted Stock—Restricted stock awards made under the 1992 Plan are subject to such restrictions, terms and conditions, including forfeitures, if any, as may be determined by the Committee.
Restricted stock awards generally vest over three years.2004 Long-Term Incentive Plan Under the Noble Energy, Inc.  2004 Long-Term Incentive Plan (the 2004 LTIP), the Committee may make incentive awards to our key employees and those of our subsidiaries.
Incentive compensation is based upon the attainment of specific market and performance goals established by the Committee.
Awards may be in the form of stock options or restricted stock or in the form of performance units or other incentive measurements providing for the payment of bonuses in cash, or in any combination thereof, as determined by the Committee in its discretion.
Stock options granted and restricted stock awarded under the 2004 LTIP are granted and awarded pursuant to the terms of the 1992 Plan.
These awards are accounted for in accordance with the provisions of SFAS 123(R) which provides for the grant-date fair value of the awards to be recognized in the statement of operations over the service period.
Our cash based performance units are accounted for under SFAS No.5, “Accounting for Contingencies” and are excluded from the provisions of SFAS 123(R).
(1) The North Sea includes acreage in the UK and the Netherlands.
In 2008, we sold our interest in Norway acreage consisting of approximately 411,000 gross (127,000 net) undeveloped acres.
(2) Other International includes India and Cyprus.
(3) Approximately 258,000 gross acres (176,000 net acres) will expire in 2009, 662,000 gross acres (385,000 net acres) will expire in 2010, and 1,370,000 gross acres (1,285,000 net acres) will expire in 2011 if production is not established or we take no other action to extend the terms.
Developed acreage is comprised of leased acres that are within an area spaced by or assignable to a productive well.
Undeveloped acreage is comprised of leased acres with defined remaining terms and not within an area spaced by or assignable to a productive well.
A gross acre is any leased acre in which a working interest is owned.
A net acre is comprised of the total of the owned working interest(s) in a gross acre expressed in a fractional format.
Drilling Activity—The results of crude oil and natural gas wells drilled and completed for each of the last three years were as follows:
## Table 2 ##
(1) Excludes wells drilled but not yet completed.
(2) Our assets in Argentina were sold February 2008.
A productive well is an exploratory or a development well that is not a dry well.
A dry well (hole) is an exploratory or a development well found to be incapable of producing either oil or gas in sufficient quantities to justify completion as an oil or gas well.
An exploratory well is a well drilled to find and produce crude oil or natural gas in an unproved area, to find a new reservoir in a field previously found to be productive of crude oil or natural gas in another reservoir, or to extend a known reservoir.
A development well, for purposes of the table above and as defined in the rules and regulations of the SEC, is a well drilled within the proved area of a crude oil or natural gas reservoir to the depth of a stratigraphic horizon known to be productive.
The number of wells drilled refers to the number of wells completed at any time during the respective year, regardless of when drilling was initiated.
Completion refers to the installation of
Table of Contents Index to Financial Statements Noble Energy, Inc.  Notes to Consolidated Financial Statements
## Table 3 ##
Restricted Stock Awards Awards of time-vested restricted stock (shares subject to service conditions) are valued at the price of our common stock at the date of award.
The fair value of the market based restricted stock awards was estimated on the date of award using a Monte Carlo valuation model that uses the assumptions in the following table.
The Monte Carlo valuation model is based on random projections of stock price paths and must be repeated numerous times to achieve a probabilistic assessment.
Expected volatility represents the extent to which our stock price is expected to fluctuate between now and the award’s anticipated term.
We use the historical volatility of Noble Energy common stock for the three-year period ended prior to the date of award.
The risk-free rate is based on a three-year period for U. S.  Treasury securities as of the year ended prior to the date of award.
The assumptions used in valuing market based restricted stock awards granted were as follows:

Tables referenced above, in order (Table 0 first):
<table><tr><td></td><td>Year Ended December</td></tr><tr><td><i>$ in millions</i></td><td>2018</td><td>2017</td><td>2016</td></tr><tr><td>Equity securities</td><td>$4,455</td><td>$4,578</td><td>$2,573</td></tr><tr><td>Debt securities and loans</td><td>3,795</td><td>2,660</td><td>1,689</td></tr><tr><td>Total net revenues</td><td>8,250</td><td>7,238</td><td>4,262</td></tr><tr><td>Provision for credit losses</td><td>674</td><td>657</td><td>182</td></tr><tr><td>Operating expenses</td><td>3,365</td><td>2,796</td><td>2,386</td></tr><tr><td>Pre-taxearnings</td><td>$4,211</td><td>$3,785</td><td>$1,694</td></tr></table>
<table><tr><td></td><td colspan="3">Year Ended December 31,</td></tr><tr><td></td><td>2008</td><td>2007</td><td>2006</td></tr><tr><td></td><td colspan="3">(in millions)</td></tr><tr><td>Stock-based compensation expense included in</td><td></td><td></td><td></td></tr><tr><td>General and administrative expense</td><td>$38</td><td>$25</td><td>$11</td></tr><tr><td>Exploration expense and other</td><td>1</td><td>2</td><td>1</td></tr><tr><td>Total stock-based compensation expense</td><td>$39</td><td>$27</td><td>$12</td></tr><tr><td>Tax benefit recognized</td><td>$-15</td><td>$-10</td><td>$-4</td></tr></table>
<table><tr><td></td><td colspan="3">Net Exploratory Wells</td><td colspan="3">Net Development Wells</td></tr><tr><td></td><td>Productive</td><td>Dry</td><td>Total</td><td>Productive-1</td><td>Dry</td><td>Total</td></tr><tr><td>Year Ended December 31,2008</td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>United States</td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Northern Region</td><td>1.0</td><td>-</td><td>1.0</td><td>837.2</td><td>42.0</td><td>879.2</td></tr><tr><td>Southern Region</td><td>14.6</td><td>2.0</td><td>16.6</td><td>30.9</td><td>2.0</td><td>32.9</td></tr><tr><td>West Africa</td><td>1.3</td><td></td><td>1.3</td><td>-</td><td>-</td><td>-</td></tr><tr><td>North Sea</td><td>-</td><td>0.4</td><td>0.4</td><td>0.6</td><td>0.3</td><td>0.9</td></tr><tr><td>Israel</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td></tr><tr><td>Suriname</td><td>-</td><td>0.5</td><td>0.5</td><td>-</td><td>-</td><td>-</td></tr><tr><td>Total</td><td>16.9</td><td>2.9</td><td>19.8</td><td>868.7</td><td>44.3</td><td>913.0</td></tr><tr><td>Year Ended December 31,2007</td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>United States</td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Northern Region</td><td>13.9</td><td>1.9</td><td>15.8</td><td>738.0</td><td>24.5</td><td>762.5</td></tr><tr><td>Southern Region</td><td>0.3</td><td>2.6</td><td>2.9</td><td>19.6</td><td>3.1</td><td>22.7</td></tr><tr><td>West Africa</td><td>2.6</td><td>0.5</td><td>3.1</td><td>-</td><td>-</td><td>-</td></tr><tr><td>North Sea</td><td>0.5</td><td>-</td><td>0.5</td><td>-</td><td>-</td><td>-</td></tr><tr><td>Israel</td><td>-</td><td>-</td><td>-</td><td>0.4</td><td>-</td><td>0.4</td></tr><tr><td>Argentina-2</td><td>-</td><td>0.1</td><td>0.1</td><td>6.7</td><td>-</td><td>6.7</td></tr><tr><td>Total</td><td>17.3</td><td>5.1</td><td>22.4</td><td>764.7</td><td>27.6</td><td>792.3</td></tr><tr><td>Year Ended December 31,2006</td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>United States</td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Northern Region</td><td>5.5</td><td>4.6</td><td>10.1</td><td>521.4</td><td>4.6</td><td>526.0</td></tr><tr><td>Southern Region</td><td>0.8</td><td>4.4</td><td>5.2</td><td>145.2</td><td>0.9</td><td>146.1</td></tr><tr><td>West Africa</td><td>-</td><td>0.4</td><td>0.4</td><td>1.8</td><td>-</td><td>1.8</td></tr><tr><td>North Sea</td><td>-</td><td>-</td><td>-</td><td>1.1</td><td>-</td><td>1.1</td></tr><tr><td>Argentina-2</td><td>-</td><td>-</td><td>-</td><td>7.6</td><td>-</td><td>7.6</td></tr><tr><td>Total</td><td>6.3</td><td>9.4</td><td>15.7</td><td>677.1</td><td>5.5</td><td>682.6</td></tr></table>
<table><tr><td></td><td colspan="2">Year Ended December 31,</td></tr><tr><td></td><td>2016</td><td>2015</td></tr><tr><td>Number of Simulations</td><td>500,000</td><td>500,000</td></tr><tr><td>Expected Volatility</td><td>38%</td><td>30%</td></tr><tr><td>Risk-Free Rate</td><td>1.0%</td><td>0.8%</td></tr></table>

Question: What is the total value of Northern Region, Southern Region, West Africa and North Sea for Productive of Net Exploratory Wells in 2007?
Answer: 17.3
Reasoning program: add(13.9,0.3), add(#0,2.6), add(#1,0.5)