UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 8-K

CURRENT REPORT PURSUANT
TO SECTION 13 OR 15(D) OF THE
SECURITIES EXCHANGE ACT OF 1934

Date of report (Date of earliest event reported)           May 2, 2006          

Martin Marietta Materials, Inc.

(Exact Name of Registrant as Specified in Its Charter)

North Carolina

(State or Other Jurisdiction of Incorporation)

1-12744		56-1848578
(Commission File Number)		(IRS Employer Identification No.)
2710 Wycliff Road, Raleigh, North Carolina		27607
(Address of Principal Executive Offices)		(Zip Code)

(919) 781-4550

(Registrant’s Telephone Number, Including Area Code)

Not Applicable

(Former Name or Former Address, if Changed Since Last Report)

     Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

     o Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

     o Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

     o Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

     o Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 2.02 Results of Operations and Financial Condition.

On May 2, 2006, the Corporation announced financial results for the first quarter ended March 31, 2006. The press release, dated May 2, 2006, is furnished as Exhibit 99.1 to this report and is incorporated by reference herein.

Item 7.01 Regulation FD Disclosure.

On May 2, 2006, the Corporation announced financial results for the first quarter ended March 31, 2006. The press release, dated May 2, 2006, is furnished as Exhibit 99.1 to this report and is incorporated by reference herein. Additional information about the quarter, and the Corporation’s use of non-GAAP financial measures, which is available on the Corporation’s Web site at www.martinmarietta.com by clicking the heading “Financials”, in the “Investors” section and then clicking the quick link “Non-GAAP Financial Measures”, is furnished as Exhibit 99.2 to this report and is incorporated by reference herein.

The Corporation will host an online Web simulcast of its first-quarter 2006 earnings conference call on Tuesday, May 2, 2006. The live broadcast of the Corporation’s conference call will begin at 2 p.m., Eastern Time, on May 2, 2006. An online replay will be available approximately two hours following the conclusion of the live broadcast. A link to these events will be available at the Corporation’s Web site at www.martinmarietta.com. For those investors without online web access, the conference call may also be accessed by calling 913-981-5542 confirmation number 4533317. Additional information about the Corporation’s use of non-GAAP financial measures, as well as certain other financial or statistical information the Corporation may present at the conference call, will be provided on the Corporation’s Web site.

Item 9.01 Financial Statements and Exhibits.

(c) Exhibits

99.1		Press Release dated May 2, 2006, announcing financial results for the first quarter ended March 31, 2006.
99.2		Additional information about Non-GAAP Financial Measures available on the Corporation’s Web site.

SIGNATURES

     Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

		MARTIN MARIETTA MATERIALS, INC.                     (Registrant)
Date:      May 2, 2006		By:		/s/ Anne H. Lloyd
				Anne H. Lloyd, Senior Vice President and Chief Financial Officer

EXHIBIT INDEX

Exhibit No.		Description
99.1		Press Release dated May 2, 2006, announcing financial results for the first quarter ended March 31, 2006.
99.2		Additional information about Non-GAAP Financial Measures available on the Corporation’s Web site.

EXHIBIT 99.1

FOR IMMEDIATE RELEASE		Contact:		Anne H. Lloyd Senior Vice President, Chief Financial Officer, and Treasurer (919) 783-4660 www.martinmarietta.com

MARTIN MARIETTA MATERIALS, INC.
ANNOUNCES RECORD FIRST-QUARTER EARNINGS OF $0.66 PER SHARE

PRICING AND VOLUME GROWTH LEAD TO IMPROVED MARGINS AND EARNINGS

RALEIGH, North Carolina (May 2, 2006) — Martin Marietta Materials, Inc. (NYSE:MLM), today announced financial results for the first quarter ended March 31, 2006, reporting record net sales, net earnings and earnings per share. Notable items were:

	•		Earnings per diluted share of $0.66 compared with $0.15 in the prior-year quarter
	•		Net sales of $424 million, up 25% compared with the prior-year quarter
	•		Heritage aggregates pricing up 15% and volume up 8.5%
	•		Consolidated operating margin up 630 basis points over prior-year quarter
	•		Magnesia Specialties operating earnings up 63% over prior-year quarter
	•		Repurchased 414,000 shares of common stock for $40 million

Management Commentary
Stephen P. Zelnak, Jr., Chairman and CEO of Martin Marietta Materials, stated, “We were very pleased with our first-quarter results where favorable weather, continued increase in demand, strong pricing and good cost management led to our eleventh consecutive quarter of improved operating margins compared with the prior year’s comparable quarter. Shipments increased in most of the Corporation’s markets with North Carolina, Texas and the Gulf Coast Region experiencing greater than 10% increases in shipment volume. Demand for aggregates products used in road building, commercial construction and residential construction, in selected markets, drove the increase in shipments. Aggregates pricing has increased across all markets. Local market demand/supply and transportation characteristics have led to significant price improvements in many areas. Favorable weather during the quarter, most notably in January and late March, also contributed to the record first-quarter performance.

“The increases in aggregates shipments and pricing, coupled with our focus on cost management, resulted in a 610-basis-point improvement in aggregates operating margin as a percentage of net sales, in spite of the rising costs of diesel fuel, repair and supply parts, and freight costs embedded in the Corporation’s long-haul transportation network. In fact, embedded freight costs per ton increased 22% when compared with the prior year’s first quarter.

“First-quarter results for our Specialty Products segment, which includes the Magnesia Specialties and Structural Composites businesses, were very positive. Magnesia Specialties’ sales grew 24% as a result of improved pricing and volume of dolomitic lime to the steel industry and chemicals products to a variety of end users. Earnings from operations at Magnesia Specialties were $8.2 million compared with $5.1 million in the prior-year period. Specialty Products results for the first quarter included a pretax loss on operations in the Structural Composites business of $1.3 million in 2006 compared with $2.6 million in 2005.

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MLM Reports First-Quarter Results
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May 2, 2006

“Selling, general and administrative expenses, as a percentage of net sales for the quarter, declined from 9.4% in 2005 to 8.5% in 2006. The decline in the expense ratio reflects our efforts to leverage our overhead structure and improve administrative efficiency, partially offset by higher incentive compensation costs and the impact of expensing stock options. Total stock-based compensation expense for the quarter was $2.2 million in 2006 compared with $0.8 million in 2005. The initial expensing of stock options increased selling, general and administrative expenses by $1.1 million during the quarter.

“The first quarter included $2.1 million of nonrecurring income from an award in connection with a land condemnation, as reported in other operating income and expenses, net.

“Our strong cash flow positions us well to use excess cash in ways that are beneficial to our shareholders, which may include increasing capital expenditures on high return, internal growth projects, voluntary pension plan contributions, further stock repurchases and increases in the common stock dividend. We continued to repurchase common stock during the quarter by acquiring 414,000 shares at an aggregate cost of $40 million. We also increased our capital investments by $27.2 million compared with the prior-year quarter as we worked on major plant projects that increase capacity and are expected to reduce production costs. Our objective continues to be to increase shareholder returns through the effective utilization of excess cash.

2006 Outlook
“The outlook for the Aggregates business for 2006 is positive. We currently expect aggregates shipments volume to increase 3% to 4% and aggregates pricing to increase 11% to 12.5%. We expect the Aggregates segment operating margin to increase approximately 300 basis points. The Magnesia Specialties business is expected to generate between $30 million and $32 million in pretax earnings. We continue working on our goal of increasing revenues in the Structural Composites business to a level that will support breakeven operations. However, a modest loss from operations is more likely in 2006.

“With this backdrop, we currently expect net earnings per diluted share for the second quarter to range from $1.50 to $1.70 and we are increasing our range for the year to $5.30 to $5.60, inclusive of $0.05 to $0.07 per diluted share for the initial expensing of stock options under FAS 123(R), Share-Based Payment.”

RISKS TO EARNINGS EXPECTATIONS
The level of aggregates demand in the Corporation’s end-use markets, the rate and breadth of aggregates mid-year price increases and the management of the costs of production will affect profitability in the aggregates business. Production cost in the aggregates business is sensitive to the cost of energy, the costs of repair and supply parts and the start-up costs for large-scale plant projects coming on line in 2006. The availability of transportation in the Corporation’s long-haul network, particularly the availability of barges on the Mississippi River system and the availability of rail cars and locomotive power to move trains, affects the Corporation’s ability to efficiently transport material into certain markets, most notably Texas and the Gulf Coast Region. The Magnesia Specialties business is sensitive to changes in natural gas prices and is dependent on the steel industry for its sales of dolomitic lime. The Structural Composites business is a start-up operation and is dependent on the level and timing of military and commercial orders for composite panel products. Earnings for 2006 may be affected by adverse weather patterns, particularly the increase in hurricane activity predicted along the East Coast of the United States. Also, changes in the market price of the Corporation’s common stock will have an impact on the valuation of stock-based compensation awards issued in 2006.

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MLM Reports First-Quarter Results
Page 3
May 2, 2006

SEGMENT FINANCIAL HIGHLIGHTS
Net sales for the Aggregates division for the first quarter were $383.0 million, a 25% increase over 2005 first-quarter sales of $307.7 million. Aggregates volume at heritage locations was up 8.5% while pricing increased 14.9%. Inclusive of acquisitions and divestitures, aggregates pricing increased 14.7% and aggregates shipments increased 7.9%. The division’s earnings from operations for the quarter were $44.4 million in 2006 versus $17.0 million in the year-earlier period.

Specialty Products’ first-quarter net sales of $41.4 million increased 36% over prior-year net sales of $30.5 million. Earnings from operations for the first quarter were $6.9 million compared with $2.5 million in the year-earlier period.

ACCOUNTING CHANGES
Effective January 1, 2006, the Corporation adopted Statement of Financial Accounting Standards No. 123 (revised 2004), Share-Based Payment (“FAS 123(R)”). The impact of adopting FAS 123(R) reduced diluted earnings per share by $0.01 for the quarter ended March 31, 2006.

Effective January 1, 2006, the Corporation adopted Emerging Issues Task Force Issue 04-06, Accounting for Stripping Costs in the Mining Industry (“EITF 04-06”), which required the write off of capitalized stripping costs as of January 1, 2006. The adoption reduced retained earnings by $4.9 million, which is net of the write off of a $3.2 million related deferred income tax liability.

***************************

CONFERENCE CALL INFORMATION
The Company will host an online Web simulcast of its first-quarter 2006 earnings conference call later today (May 2, 2006). The live broadcast of Martin Marietta Materials’ conference call will begin at 2 p.m. Eastern Time today. An online replay will be available approximately two hours following the conclusion of the live broadcast. A link to these events will be available at the Company’s Web site.

For those investors without online web access, the conference call may also be accessed by calling 913-981-5542, confirmation number 4533317.

For more information about Martin Marietta, refer to our Web site at www.martinmarietta.com.

Martin Marietta is the nation’s second largest producer of construction aggregates, a leading producer of magnesia-based chemical products and is developing structural composites products for use in a wide variety of industries.

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May 2, 2006

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MLM Reports First-Quarter Results
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May 2, 2006

MARTIN MARIETTA MATERIALS, INC.
Unaudited Statement of Earnings
(In millions, except per share amounts)

		Three Months Ended
		March 31,
		2006				2005
Net sales		$	424.4			$	338.2
Freight and delivery revenues			59.6				51.5
Total revenues			484.0				389.7
Cost of sales			340.4				288.5
Freight and delivery costs			59.6				51.5
Cost of revenues			400.0				340.0
Gross profit			84.0				49.7
Selling, general and administrative expenses			36.2				31.8
Research and development			0.2				0.2
Other operating (income) and expenses, net			(3.7	)			(1.8	)
Earnings from operations			51.3				19.5
Interest expense			10.0				10.8
Other nonoperating (income) and expenses, net			(2.1	)			(2.2	)
Earnings before taxes on income			43.4				10.9
Income tax expense			13.7				2.3
Earnings from continuing operations			29.7				8.6
Discontinued operations:
Gain (Loss) on discontinued operations, net of related tax expense (benefit) of $0.6 and $(0.7), respectively			1.3				(1.5	)
Net Earnings		$	31.0			$	7.1
Net earnings (loss) per share:
Basic from continuing operations		$	0.65			$	0.18
Discontinued operations			0.03				(0.03	)
		$	0.68			$	0.15
Diluted from continuing operations		$	0.63			$	0.18
Discontinued operations			0.03				(0.03	)
		$	0.66			$	0.15
Dividends per common share		$	0.23			$	0.20
Average number of shares outstanding:
Basic			45.8				47.1
Diluted			46.8				47.7

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MLM Reports First-Quarter Results
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May 2, 2006

MARTIN MARIETTA MATERIALS, INC.
Unaudited Financial Highlights
(In millions)

		Three Months Ended
		March 31,
		2006				2005
Net sales:
Aggregates		$	383.0			$	307.7
Specialty Products			41.4				30.5
Total		$	424.4			$	338.2
Gross profit:
Aggregates		$	74.4			$	44.3
Specialty Products			9.6				5.4
Total		$	84.0			$	49.7
Selling, general, and administrative expenses:
Aggregates		$	33.4			$	29.0
Specialty Products			2.8				2.8
Total		$	36.2			$	31.8
Other operating (income) and expenses, net:
Aggregates		$	(3.4	)		$	(1.7	)
Specialty Products			(0.3	)			(0.1	)
Total		$	(3.7	)		$	(1.8	)
Earnings from operations:
Aggregates		$	44.4			$	17.0
Specialty Products			6.9				2.5
Total		$	51.3			$	19.5
Depreciation		$	30.7			$	31.0
Depletion			0.9				0.9
Amortization			1.1				1.4
		$	32.7			$	33.3
Earnings Before Interest, Income Taxes, Depreciation, Depletion and Amortization (EBITDA) (1)		$	88.0			$	52.8

(1)

EBITDA is a widely accepted financial indicator of a company’s ability to service and/or incur indebtedness. EBITDA is not defined by generally accepted accounting principles and, as such, should not be construed as an alternative to net earnings or operating cash flow. For further information on EBITDA, refer to the Corporation’s Web site at www.martinmarietta.com.

A reconciliation of Net Cash Provided by Operating Activities to EBITDA is as follows:

		Three Months Ended
		March 31,
		2006				2005
Net Cash Provided by Operating Activities		$	32.5			$	30.0
Changes in operating assets and liabilities, net of effects of acquisitions and divestitures			20.1				12.0
Other items, net			11.1				(1.6	)
Income tax expense			14.3				1.6
Interest expense			10.0				10.8
EBITDA		$	88.0			$	52.8

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MLM Reports First-Quarter Results
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May 2, 2006

MARTIN MARIETTA MATERIALS, INC.
Balance Sheet Data
(In millions)

		March 31,				December 31,				March 31,
		2006				2005				2005
		(Unaudited)								(Unaudited)
ASSETS
Cash and cash equivalents		$	31.2			$	76.7			$	103.1
Investments			—				25.0				—
Accounts receivable, net			241.6				225.0				220.4
Inventories, net			241.4				222.7				224.9
Other current assets			70.7				52.6				37.1
Property, plant and equipment, net			1,205.5				1,166.4				1,106.7
Other noncurrent assets			56.6				76.9				71.7
Intangible assets, net			588.0				588.0				590.2
Total assets		$	2,435.0			$	2,433.3			$	2,354.1
LIABILITIES AND SHAREHOLDERS’ EQUITY
Current maturities of long-term debt		$	0.6			$	0.9			$	0.9
Other current liabilities			214.9				199.2				197.8
Long-term debt (excluding current maturities)			705.9				709.2				710.3
Other noncurrent liabilities			326.6				350.3				326.5
Shareholders’ equity			1,187.0				1,173.7				1,118.6
Total liabilities and shareholders’ equity		$	2,435.0			$	2,433.3			$	2,354.1

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MLM Reports First-Quarter Results
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May 2, 2006

MARTIN MARIETTA MATERIALS, INC.
Unaudited Statement of Cash Flows
(In millions)

		Three Months Ended
		March 31,
		2006				2005
Net earnings		$	31.0			$	7.1
Adjustments to reconcile net earnings to cash provided by operating activities:
Depreciation, depletion and amortization			32.7				33.3
Share-based compensation expense			2.2				0.8
Excess tax benefits from share-based compensation			(7.2	)			1.8
(Gains) Losses on sales of assets			(2.8	)			0.3
Other items, net			(0.9	)			(1.7	)
Deferred income taxes			(2.4	)			0.4
Changes in operating assets and liabilities:
Accounts receivable, net			(16.6	)			(0.9	)
Inventories, net			(18.8	)			(13.1	)
Accounts payable			(0.1	)			(0.2	)
Other assets and liabilities, net			15.4				2.2
Net cash provided by operating activities			32.5				30.0
Investing activities:
Additions to property, plant and equipment			(74.4	)			(47.2	)
Acquisitions, net			(2.8	)			(3.9	)
Proceeds from divestitures of assets			18.3				11.7
Proceeds from sale of investments			25.0				—
Railcar construction advances			(17.6	)			—
Net cash used for investing activities			(51.5	)			(39.4	)
Financing activities:
Repayments of long-term debt			(0.3	)			(0.4	)
Change in bank overdraft			4.0				(1.7	)
Dividends paid			(10.6	)			(9.4	)
Repurchases of common stock			(40.0	)			(44.3	)
Issuance of common stock			13.2				6.7
Excess tax benefits from share-based compensation			7.2				—
Net cash used for financing activities			(26.5	)			(49.1	)
Net decrease in cash and cash equivalents			(45.5	)			(58.5	)
Cash and cash equivalents, beginning of period			76.7				161.6
Cash and cash equivalents, end of period		$	31.2			$	103.1

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MLM Reports First-Quarter Results
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May 2, 2006

MARTIN MARIETTA MATERIALS, INC.
Unaudited Operational Highlights

		Three Months Ended
		March 31, 2006
		Volume				Pricing
Volume/Pricing Variance (1)
Heritage Aggregates Operations (2)			8.5	%			14.9	%
Aggregates Division (3)			7.9	%			14.7	%
		Three Months Ended
		March 31,
		2006				2005
Shipments (tons in thousands)
Heritage Aggregates Operations (2)			42,571				39,228
Acquisitions			—				—
Divestitures (4)			18				248
Aggregates Division (3)			42,589				39,476

(1)		Volume/pricing variances reflect the percentage increase from the comparable period in the prior year.
(2)		Heritage Aggregates operations exclude acquisitions that have not been included in prior-year operations for a full year and divestitures.
(3)		Aggregates division includes all acquisitions from the date of acquisition and divestitures through the date of disposal.
(4)		Divestitures include the tons related to divested operations up to the date of divestiture.

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Exhibit 99.2

Additional Information about Non-GAAP Financial Measures Available on the Corporation’s Web site

From time to time management may publicly disclose certain “non-GAAP financial measures” in the course of our financial presentations, earnings releases, earnings conference calls, and otherwise. For these purposes, the SEC defines a “non-GAAP financial measure” as a numerical measure of historical or future financial performance, financial position, or cash flows that excludes amounts, or is subject to adjustments that effectively exclude amounts, included in the most directly comparable measure calculated and presented in accordance with GAAP in financial statements, and vice versa for measures that include amounts, or is subject to adjustments that effectively include amounts, that are excluded from the most directly comparable measure so calculated and presented. For these purposes, “GAAP” refers to generally accepted accounting principles in the United States.

Non-GAAP financial measures disclosed by management are provided as additional information to investors in order to provide them with an alternative method for assessing our financial condition and operating results. These measures are not in accordance with, or a substitute for, GAAP, and may be different from or inconsistent with non-GAAP financial measures used by other companies.

Pursuant to the requirements of Regulation G, whenever we refer to a non-GAAP financial measure, we will also generally present, on this Web site, the most directly comparable financial measure calculated and presented in accordance with GAAP, along with a reconciliation of the differences between the non-GAAP financial measure we reference with such comparable GAAP financial measure.

One such non-GAAP financial measure we may present from time to time is Earnings before Interest, Income Taxes, Depreciation, Depletion and Amortization (“EBITDA”). EBITDA is not a measure of financial performance under GAAP. Accordingly, it should not be considered as a substitute for net earnings (loss), operating earnings (loss), cash flow provided by operating activities or other income or cash flow data prepared in accordance with GAAP. However, the Corporation’s management believes that EBITDA may provide additional information with respect to the Corporation’s performance or ability to meet its future debt service, capital expenditures and working capital requirements. Because EBITDA excludes some, but not all, items that affect net earnings and may vary among companies, the EBITDA presented by Martin Marietta Materials may not be comparable to similarly titled measures of other companies. Martin Marietta Materials calculates EBITDA as:

Net earnings (loss) before interest expense, income tax expense (benefit) and depreciation, depletion and amortization expense. EBITDA is also before the cumulative effect of a change in accounting principle, if applicable.

The following tables present Martin Marietta Materials’ reconciliations between net income and net cash provided by operating activities to EBITDA for the years 1994 to 2005, quarterly and year-to-date periods in 2005 and 2006 (see Web site for tables)

Other non-GAAP measures we may present from time to time are gross margin excluding freight and delivery revenues and operating margin excluding freight and delivery revenues. The Corporation calculates gross margin excluding freight and delivery revenues as gross profit divided by net sales and operating margin excluding freight and delivery revenues as earnings from operations divided by net sales. The Corporation presents these ratios calculated based on net sales as opposed to total revenues, as it is consistent with the basis by which management reviews the Corporation’s operating results. Further, management believes it is consistent with the basis by which investors analyze the Corporation’s operating results given that freight and delivery revenues represent pass-through income and have no mark-up. Gross margin and operating margin calculated as percentages of total revenues represent the most directly comparable financial measures calculated in accordance with generally accepted accounting principles. The following tables calculate gross margin and operating margin in accordance with generally accepted accounting principles, reconcile total revenues to net sales and calculate gross margin excluding freight and delivery revenues and operating margin excluding freight and delivery revenues for the three months ended March 31, 2006 and 2005 (see Web site for tables)

An additional non-GAAP measure we may present from time to time is debt-to-capitalization, net of available cash. The Corporation calculates the ratio by using adjusted debt, as it believes using available cash to hypothetically reduce outstanding debt provides a more appropriate evaluation of the Corporation’s leverage to incur additional debt. The majority of the Corporation’s debt is not redeemable prior to maturity. The following tables calculate the Corporation’s debt-to-capitalization ratio at March 31, 2006 and March 31, 2005 using total debt and total capital per the balance sheet, reconciles total capital using adjusted debt to total capital per the balance sheet and calculates total debt-to-capitalization, net of available cash (see Web site for tables)

Another non-GAAP financial measure we may present from time to time is Free Cash Flow. Martin Marietta Materials calculates Free Cash Flow as:

Net cash provided by operating activities less capital expenditures and dividends paid. Proceeds from divestitures of assets are then added to determine Free Cash Flow.

The following table reconciles net cash provided by operating activities to free cash flow for the years 2000 to 2005 (see Web site for table)

The following tables reconcile:

	•		Earnings per diluted share for the year ended December 31, 2005 to earnings per diluted share excluding one-time favorable tax items and the pro forma effect of expensing stock options; and
	•		Earnings per diluted share to earnings per diluted share excluding discrete income tax events for the quarters ended September 30, 2005 and 2004. (see Web site for tables)