Exhibit 99.1

UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL DATA FOR NYSE GROUP

The following unaudited pro forma condensed combined financial data and explanatory notes present how the consolidated financial statements of NYSE Group may have
appeared had Archipelago, PCX Holdings and the NYSE actually been combined at earlier dates. The unaudited pro forma condensed combined financial data shows the impact of the combinations on the
companies' respective historical financial positions and results of operations under the purchase method of accounting with Archipelago treated as the acquiror of PCX Holdings and the NYSE treated as
the acquiror of Archipelago, and as if the acquisition of PCX Holdings by Archipelago and the acquisition of Archipelago by the NYSE had been completed on January 1, 2005 for statement of
income purposes and on December 31, 2005 for statement of financial condition purposes.

On
September 26, 2005, Archipelago completed the acquisition of PCX Holdings for a total purchase price of approximately $94.0 million consisting of a $90.9 million
cash payment to PCX Holdings stockholders and certain PCX Holdings employees, and approximately $3.1 million of direct costs incurred by Archipelago as part of this acquisition. The
$90.9 million cash payment represented the total dollar value of 1,645,415 shares of Archipelago common stock held by the Pacific Exchange at the time of the closing, or $66.3 million
(calculated based on the average closing price of Archipelago's stock price on NYSE Arca (formerly known as ArcaEx) for the ten trading days prior to the acquisition of PCX Holdings), plus
$24.6 million.

In
the merger of the NYSE and Archipelago, a wholly owned subsidiary of NYSE Group merged with and into Archipelago, and Archipelago common stockholders had the right to receive one
share of NYSE Group common stock for each share of Archipelago common stock that they owned. In addition, a successor of the NYSE merged with and into a wholly owned subsidiary of NYSE Group, and the
NYSE members had the right to receive $300,000 in cash and 80,177 shares NYSE Group common stock. In the merger, the NYSE members had the opportunity to make the cash election to increase the cash
portion (and decrease the stock portion) of their consideration, or a stock election to increase the stock portion (and decrease the cash portion) of their consideration. These elections, however,
were subject to proration so that the total cash consideration paid to NYSE members in the merger did not exceed, in the aggregate, $409.8 million. Restricted stock units and stock options of
Archipelago common stock at the effective time of the merger were converted into restricted stock units and stock options of our common stock on a one-for-one basis.

For
accounting purposes, the acquisition of PCX Holdings by Archipelago is treated under the purchase method of accounting and PCX Holdings' assets acquired and liabilities assumed were
recorded at their estimated fair value. The NYSE and Archipelago merger and related transactions will also be treated under the purchase method of accounting for accounting purposes, and Archipelago's
assets acquired and liabilities assumed will be recorded at their fair value.

The
fair value of NYSE Group common stock issued to Archipelago stockholders in the merger is the purchase consideration in the merger. For purposes of the pro forma condensed combined
financial data, we have assumed that the stock price of Archipelago is $22.43 per share (based on the average closing stock price for the five-day period beginning two days before and
ending two days after April 20, 2005, the date the merger was agreed to and announced) and that 47,838,000 shares of Archipelago common stock were outstanding at the date of the completion of
the merger (including 49,640,000 shares issued less approximately 1,802,000 shares held in treasury). The closing price of Archipelago common stock on March 7, 2006, the date of the completion
of the NYSE and Archipelago merger, was $64.25 per share.

The
allocations of the respective purchase price to PCX Holdings and Archipelago's assets, including intangible assets, and liabilities are only preliminary allocations based on
estimates of fair values and will change when estimates are finalized. Among the provisions of Statement of Financial Accounting Standards No. 141, "Business Combinations," criteria have been
established for determining

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whether
intangible assets should be recognized separately from goodwill. Statement of Financial Accounting Standards No. 142, "Goodwill and Other Intangible Assets" ("SFAS 142")
provides, among other guidelines, that goodwill and intangible assets with indefinite lives will not be amortized, but rather are tested for impairment on at least an annual basis.

The
unaudited pro forma condensed combined statements of income do not include any potential revenue and cost synergies.

The
unaudited pro forma condensed combined statement of financial condition as of December 31, 2005 combines the December 31, 2005 historical statement of financial
condition of the NYSE and the December 31, 2005 historical statement of financial condition of Archipelago and assumes that the merger of NYSE and Archipelago took place on that date. The
unaudited pro forma condensed combined statement of operations for the fiscal year ended December 31, 2005 assumes that both business combinations took place on January 1, 2005. The
fiscal years of the NYSE, Archipelago and PCX Holdings end on December 31. Therefore, the accompanying unaudited pro forma condensed
combined statement of operations for the year ended December 31, 2005 combines the historical statements of operations of NYSE, Archipelago and PCX Holdings for the fiscal year ended
December 31, 2005. Reclassifications have been made to the historical financial statements of NYSE, Archipelago and PCX Holdings to conform to the presentation used by NYSE Group.

The
pro forma condensed combined financial data shown under this heading is unaudited, is presented for informational purposes only, and is not necessarily indicative of the financial
position or results of operations that would actually have occurred had the acquisition of PCX Holdings by Archipelago and the merger of NYSE and Archipelago been consummated as of the dates or at the
beginning of the periods presented, nor is it necessarily indicative of future operating results or financial position. The unaudited pro forma condensed combined financial data shown under this
heading and the accompanying notes should be read together with:



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NYSE GROUP, INC.  UNAUDITED PRO FORMA CONDENSED COMBINED STATEMENT  OF FINANCIAL CONDITION  AS OF DECEMBER 31, 2005  (In thousands)

|                            |                      |                                 |                              |   |         | Pro Forma |  
|--------------------------- | -------------------- | ------------------------------- | ---------------------------- | - | ------- | --------- | -
|
|
|
|Assets                      |                      |                                 |                              |   |         |           |  
|                            | Current assets:      |                                 |                              |   |         |           |  
|                            |                      | Cash and cash equivalents       |                              | $ | 134,358 |           | $
|                            |                      | Investment and other securities |                              |   |        |           |  
|                            |                      | Receivables, net                |                              |   | 97,944  |           |  
|                            |                      | Deferred income taxes           |                              |   | 5,787   |           |  
|                            |                      | Other current assets            |                              |   | 7,976   |           |  
|                            |                      |                                 |                              |   |         |           |  
|                            |                      |                                 | Total current assets         |   |         | 246,065   |  
|Property and equipment, net |                      |                                 | 67,091                       |   |         | 343,534   |  
|Goodwill                    |                      |                                 | 131,865                      |   |         |          |  
|Intangible assets, net      |                      |                                 | 108,753                      |   |         |          |  
|Deferred income taxes       |                      |                                 | 11,863                       |   |         | 290,145   |  
|Other assets                |                      |                                 | 14,157                       |   |         | 106,249   |  
|                            |                      |                                 |                              |   |         |           |  
|                            |                      |                                 | Total assets                 |   | $       | 579,794   |  
|                            |                      |                                 |                              |   |         |           |  
|Liabilities and Equity      |                      |                                 |                              |   |         |           |  
|                            | Current liabilities: |                                 |                              |   |         |           |  
|                            |                      | Payables and accrued expenses   |                              | $ | 72,727  |           | $
|                            |                      | Section 31 fees payable         |                              |   | 57,032  |           |  
|                            |                      | Deferred revenue                |                              |   | 8,117   |           |  
|                            |                      | Deferred income taxes           |                              |   |        |           |  
|                            |                      |                                 |                              |   |         |           |  
|                            |                      |                                 | Total current liabilities    |   |         | 137,876   |  
|                            |                      | Accrued employee benefits       |                              |   |        |           |  
|                            |                      | Deferred revenue                |                              |   |        |           |  
|                            |                      | Deferred income taxes           |                              |   | 10,312  |           |  
|                            |                      | Other liabilities               |                              |   | 9,457   |           |  
|                            |                      |                                 |                              |   |         |           |  
|                            |                      |                                 | Total liabilities            |   |         | 157,645   |  
|                            |                      | Minority interest               |                              |   |        |           |  
|                            |                      | Equity                          |                              |   | 422,149 |           |  
|                            |                      |                                 |                              |   |         |           |  
|                            |                      |                                 | Total liabilities and equity |   | $       | 579,794   |  
|                            |                      |                                 |                              |   |         |           |  



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NYSE GROUP, INC.
UNAUDITED PRO FORMA CONDENSED COMBINED STATEMENT OF INCOME
YEAR ENDED DECEMBER 31, 2005
(In thousands, except per share data)

|                                                                          |                                                                   | Historical                          |         | Pro Forma |   | Historical |        | Pro Forma
|------------------------------------------------------------------------- | ----------------------------------------------------------------- | ----------------------------------- | ------- | --------- | - | ---------- | ------ | ---------
|
|Revenues                                                                  |                                                                   |                                     |         |           |   |            |        |          
|                                                                          | Transaction fees                                                  |                                     | $       | 424,981   |   | $          | 30,306 |          
|                                                                          | Listing fees                                                      |                                     |         | 494       |   |            |       |          
|                                                                          | Market data fees                                                  |                                     |         | 61,996    |   |            | 2,534  |          
|                                                                          | Data processing fees                                              |                                     |         |          |   |            |       |          
|                                                                          | Archipelago revenue:                                              |                                     |         |           |   |            |        |          
|                                                                          |                                                                   | Original consideration amortization |         |           |  |            |        | 10,215   
|                                                                          |                                                                   | Regulatory oversight                |         |           |  |            |        | 6,022    
|                                                                          |                                                                   | Registered representative fees      |         |           |  |            |        | (3,826   
|                                                                          | Regulatory fees                                                   |                                     |         |          |   |            |       |          
|                                                                          | Other                                                             |                                     |         | 10,141    |   |            | 13,458 |          
|                                                                          |                                                                   |                                     |         |           |   |            |        |          
|Total revenues                                                            |                                                                   |                                     | 497,612 |           |   | 58,709     |        |          
|                                                                          |                                                                   |                                     |         |           |   |            |        |          
|Expenses                                                                  |                                                                   |                                     |         |           |   |            |        |          
|                                                                          | Merger expenses and related executive compensation and exit costs |                                     |         | 46,127    |   |            |       |          
|                                                                          | Other employee compensation and benefits                          |                                     |         | 51,552    |   |            | 22,443 |          
|                                                                          | Liquidity payments                                                |                                     |         | 206,907   |   |            |       |          
|                                                                          | Routing and clearing fees                                         |                                     |         | 72,585    |   |            |       |          
|                                                                          | Systems and communications                                        |                                     |         | 19,512    |   |            | 5,209  |          
|                                                                          | Professional services                                             |                                     |         | 12,623    |   |            | 3,116  |          
|                                                                          | Depreciation and amortization                                     |                                     |         | 21,631    |   |            | 10,018 |          
|                                                                          | Occupancy                                                         |                                     |         | 6,708     |   |            | 3,690  |          
|                                                                          | Selling, general and administrative                               |                                     |         | 38,112    |   |            | 6,483  |          
|                                                                          |                                                                   |                                     |         |           |   |            |        |          
|Total expenses                                                            |                                                                   |                                     | 475,757 |           |   | 50,959     |        |          
|                                                                          |                                                                   |                                     |         |           |   |            |        |          
|Income (loss) before income tax provision (benefit) and minority interest |                                                                   |                                     | 21,855  |           |   | 7,750      |        |          
|Income tax provision (benefit)                                            |                                                                   |                                     | 9,349   |           |   | 3,600      |        |          
|Minority interest                                                         |                                                                   |                                     |        |           |   |           |        |          
|                                                                          |                                                                   |                                     |         |           |   |            |        |          
|Income (loss) from continuing operations                                  |                                                                   | $                                   | 12,506  |           | $ | 4,150      |        | $        
|                                                                          |                                                                   |                                     |         |           |   |            |        |          
|Basic earnings per share from continuing operations                       |                                                                   | $                                   | 0.27    |           |   |            |        |          
|                                                                          |                                                                   |                                     |         |           |   |            |        |          
|Diluted earnings per share from continuing operations                     |                                                                   | $                                   | 0.26    |           |   |            |        |          
|                                                                          |                                                                   |                                     |         |           |   |            |        |          
|Basic weighted average shares outstanding                                 |                                                                   |                                     | 46,806  |           |   |            |        |          
|                                                                          |                                                                   |                                     |         |           |   |            |        |          
|Diluted weighted average shares outstanding                               |                                                                   |                                     | 47,821  |           |   |            |        |          
|                                                                          |                                                                   |                                     |         |           |   |            |        |          

The accompanying notes are an integral part of the unaudited pro forma condensed combined financial statements.

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NYSE GROUP, INC.  NOTES TO UNAUDITED PRO FORMA CONDENSED  COMBINED FINANCIAL STATEMENTS

Note 1Basis of Presentation

The unaudited pro forma condensed combined financial statements give effect to the following:



On
September 26, 2005, Archipelago completed the acquisition of PCX Holdings. Based on the preliminary allocation of the purchase price in the PCX Holdings acquisition, the assets
and liabilities of PCX Holdings were included in Archipelago's historical consolidated statement of financial condition as of December 31, 2005. The results of operations of PCX Holdings have
been included in Archipelago's historical results of operations since October 1, 2005.

The
unaudited pro forma condensed combined financial data is presented for illustrative purposes only and is not necessarily indicative of the operating results or financial position
that would have occurred if the business combinations had been consummated during the period or as of the dates for which the pro forma data is presented, nor is it necessarily indicative of the
future operating results or financial position of the NYSE Group.

NYSE's
purchase price for Archipelago has been allocated to the assets acquired and the liabilities assumed based upon management's preliminary estimate of their respective fair values
as of the date of acquisition. Definitive allocations will be performed when estimates are finalized. Accordingly, the purchase price allocation pro forma adjustments are preliminary, have been made
solely for the purpose of providing unaudited pro forma condensed combined financial data and are subject to revision based on a final determination of fair value after the closing of the business
combination.

The
accompanying unaudited pro forma condensed combined statement of income does not include (1) any revenue from the sale of NYSE trading licenses, (2) any revenue or cost
saving synergies that may be achievable subsequent to the completion of the merger, or (3) the impact of non-recurring items directly related to the merger.

Certain
reclassifications have been made to the historical financial statements of the NYSE, Archipelago and PCX Holdings to conform to the presentation expected to be used by NYSE
Group.

Note 2Purchase Price of Archipelago

For the purpose of preparing the accompanying unaudited pro forma condensed combined statement of financial condition as of December 31, 2005, management
made the following assumptions:



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The
estimated fair value of NYSE Group securities to be issued to Archipelago stockholders to effect the merger represents the purchase consideration in the merger, which was computed as
follows:

47,838,000 shares(a)times

$22.43 per share(b)$1,073 million


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Historical cost of net assets acquired

$
422,149Elimination of Archipelago's historical goodwill and intangibles


(240,618
)Adjustment to fair value property and equipment (Note 3.6)


17,950Fair value of identifiable intangible assets (Note 3.6)


563,400Deferred tax impact of purchase accounting adjustments


(225,449
)Residual goodwill created from merger


535,568Total purchase price

$
1,073,000


Note 3Pro Forma Adjustments

|[3.1] |  | To reverse the revenue recognized by PCX Holdings in relation to its exchange facility agreement with Archipelago. In May 2001, Archipelago acquired the right to operate as the exclusive equity trading facility of
PCX Equities, including the rights to certain revenue streams comprised primarily of transaction fees, market data fees and listing fees, for an aggregate consideration of $90.0 million. Archipelago determined that this intangible asset had an
indefinite life and, as such, it is not subject to amortization. PCX Holdings deferred the recognition of a portion of the consideration over a period of five years.
|----- |  | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|[3.2] |  | To reverse the regulatory oversight revenue recognized by the Pacific Exchange and corresponding regulatory fees incurred by Archipelago. Under the terms of the facility services agreement between the Pacific Exchange and Archipelago, Pacific
Exchange provided certain regulatory services to Archipelago in return for regular payments as negotiated between the parties.                                                                                                                                                                                                                                                              
|      |  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                

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|[3.3] |  | To reverse the registered representative fee revenue recognized by Archipelago (as contra routing and clearing fees) and corresponding expense recorded at PCX Holdings (as contra revenue). Prior to the acquisition of PCX Holdings by Archipelago, PCX
Holdings forwarded a portion of the registered representative fees received from the National Association of Security Dealers to Archipelago.
|----- |  | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|[3.4] |  | To adjust the income tax provision for the effect of the pro forma adjustments based upon a combined federal, state and local corporate income tax rate of 40.0%. Deferred income tax impacts as a result of the purchase accounting adjustments were also
estimated at a $40.0% blended income tax rate.                                                                                              
|[3.5] |  | To adjust the weighted average shares outstanding to reflect the retirement of 1,645,415 shares of Archipelago common stock held by the Pacific Exchange at the time of acquisition.                                                                                                                                                                                                                   
|[3.6] |  | To adjust the book value of Archipelago fixed assets and intangible assets to their estimated fair value. The preliminary allocations included in the unaudited pro forma condensed combined financial data are as follows (in thousands):                                                                                                                                                             

Increase
in value

Estimated average
remaining useful life

Estimated annual
depreciation
expenseFixed asset class:Software

$
12,172

5 years

$
2,434Other equipment


5,778

3 years


1,926Fixed assets

$
17,950


Value

Estimated average
remaining useful life

Estimated annual
depreciation expenseIntangible asset class: National securities exchange registration

$
496,000
(a)
Indefinite


n/aCustomer relationships


31,300

20 years


1,565Trade names


36,100
(b)
20 years


1,805Intangible assets

$
563,400Total

$
581,350



$
7,730


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|[3.7] |  | As of December 31, 2005, the equity of the NYSE Group consisted of the following (in thousands):
|----- |  | ------------------------------------------------------------------------------------------------

Historical equity of the NYSE

$
799,125Less: NYSE payment to members (Note 2)


(409,800
)Less: NYSE dividend to members (Note 2)


(96,400
)Estimated fair value of Archipelago


1,073,000Total equity of NYSE Group

$
1,365,925


|[3.8] |  | To eliminate the merger costs incurred by the NYSE and Archipelago as well as related Archipelago executive compensation and NYSE exit costs to arrive at pro forma income from continuing operations. The merger costs and
related executive compensation and exit costs represent nonrecurring charges directly attributable to the merger.
|----- |  | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|[3.9] |  | To adjust the weighted average number of shares outstanding used to determine basic and diluted pro forma earnings per share based upon the exchange of shares of Archipelago common stock for the equivalent of 30% of the NYSE Group common
stock.                                                                                         

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