A summary of our consolidated quarterly operating results in 2012 and 2011 is as follows (in thousands, except unit and per unit data):

	Quarter Ended

	March 31, 2012		June 30, 2012		September 30, 2012 (3)		December 31, 2012 (1)
Revenues	$	443,492	$	529,772	$	511,348	$	549,318
Income from operations		91,501		103,886		68,561		106,184
Net income		82,486		93,881		58,733		96,126
Net income of AHGP		49,314		54,364		39,495		52,895
Basic and diluted net income per limited partner unit	$	0.82	$	0.91	$	0.66	$	0.88
Weighted average number of units outstanding—basic and diluted		59,863,000		59,863,000		59,863,000		59,863,000

	Quarter Ended

	March 31, 2011		June 30, 2011		September 30, 2011		December 31, 2011 (1)(2)
Revenues	$	423,172	$	457,855	$	487,657	$	474,519
Income from operations		102,830		106,284		111,688		89,106
Net income		94,441		97,286		103,667		90,949
Net income of AHGP		51,507		53,412		57,108		52,116
Basic and diluted net income per limited partner unit	$	0.86	$	0.89	$	0.95	$	0.87
Weighted average number of units outstanding—basic and diluted		59,863,000		59,863,000		59,863,000		59,863,000

(1): The comparability of our December 31, 2012 and 2011 quarterly results were affected by a $14.0 million and $13.6 million, respectively, decrease in the ARLP Partnership's workers' compensation liability, excluding discount rate changes, due to the completion of its annual actuarial study, which reflected a favorable development in the ARLP Partnership's disability emergence patterns and claims estimates, as well as of the establishment of credible trends for the Mettiki (WV) claims experience and resulting favorable actuarial estimate adjustments.
(2): During the quarter ended December 31, 2011, the ARLP Partnership corrected the interest rate used to account for capitalized interest to utilize the Partnership's overall borrowing rate. This correction resulted in a $10.0 million increase in property, plant and equipment (net of $1.2 million of related depreciation, depletion and amortization) and an $11.2 million offsetting decrease to interest expense ($9.4 million of which was related to prior years). Management concluded the effect of the correction was not material to prior periods, 2011 results or the trend of earnings.
(3): During the quarter ended September 30, 2012, the ARLP Partnership recorded a $19.0 million impairment of the carrying value of assets at the Pontiki mine (Note 5).