Exhibit 11.1

NewMarket Corporation and Subsidiaries

Computation of Basic and Diluted Earnings per Share

For the Years Ended December 31, 2005, 2004 and 2003

(In thousands except per share amounts)

	2005		2004		2003
Basic earnings per share
Numerator:
Income available to shareholders, as reported	$	42,381	$	33,058	$	37,053
Denominator:
Average number of shares of common stock outstanding		17,028		16,916		16,733
Basic earnings per share	$	2.49	$	1.95	$	2.21
Diluted earnings per share
Numerator:
Income available to shareholders, as reported	$	42,381	$	33,058	$	37,053
Denominator:
Average number of shares of common stock outstanding		17,028		16,916		16,733
Shares issuable upon exercise of stock options		292		283		207
		17,320		17,199		16,940
Diluted earnings per share	$	2.45	$	1.92	$	2.19

Note:

In the periods presented, NewMarket Corporation had only one class of common stock outstanding.