Exhibit A

Transactions by Reporting Persons in the last 60 days not previously reported.

Beneficial Ownership	Purchase or Sale	Quantity	Transaction Date	Price per Share (including commission)		How Effected
Relational Investors X, L.P.	Sale	11,201	8/1/2011	$	24.66	Open Market
Relational Investors, L.P.	Purchase	43,118	8/8/2011	$	20.45	Open Market
RH Fund 1, L.P.	Purchase	18,442	8/8/2011	$	20.45	Open Market
Relational Investors LLC	Purchase	23,995	8/8/2011	$	20.45	Open Market
RH Fund 6, L.P.	Purchase	11,384	8/8/2011	$	20.45	Open Market
Relational Investors VIII, L.P.	Purchase	50,453	8/8/2011	$	20.45	Open Market
Relational Investors IX, L.P.	Purchase	15,792	8/8/2011	$	20.45	Open Market
Relational Investors X, L.P.	Purchase	5,124	8/8/2011	$	20.45	Open Market
Relational Investors XV, L.P.	Purchase	5,323	8/8/2011	$	20.45	Open Market
Relational Investors XVI, L.P.	Purchase	5,240	8/8/2011	$	20.45	Open Market
Relational Investors XX, L.P.	Purchase	4,827	8/8/2011	$	20.45	Open Market
Relational Investors XXII, L.P.	Purchase	7,274	8/8/2011	$	20.45	Open Market
Relational Investors XXIII, L.P.	Purchase	6,757	8/8/2011	$	20.45	Open Market
Relational Investors LLC	Purchase	11,121	8/8/2011	$	20.45	Open Market
Relational Investors LLC	Purchase	1,962	8/8/2011	$	20.45	Open Market
Relational Coast Partners, L.P.	Purchase	2,145	8/8/2011	$	20.45	Open Market
Relational Coast Partners, L.P.	Purchase	278	8/8/2011	$	20.45	Open Market
Relational Fund Partners, L.P.	Purchase	462	8/8/2011	$	20.45	Open Market
Relational Fund Partners, L.P.	Purchase	108	8/8/2011	$	20.45	Open Market
Relational Fund Partners, L.P.	Purchase	3	8/8/2011	$	20.45	Open Market
Relational Investors Alpha Fund I, L.P.	Purchase	12,830	8/8/2011	$	20.45	Open Market
Relational Investors LLC	Purchase	31,444	8/8/2011	$	20.45	Open Market
Relational Investors, L.P.	Purchase	33,414	8/9/2011	$	20.76	Open Market
Relational Investors, L.P.	Purchase	13,546	8/9/2011	$	21.27	Open Market
Relational Investors, L.P.	Purchase	12,530	8/9/2011	$	20.60	Open Market
Relational Investors, L.P.	Purchase	208,843	8/9/2011	$	21.32	Open Market
Relational Investors, L.P.	Purchase	78,867	8/9/2011	$	21.26	Open Market
RH Fund 1, L.P.	Purchase	14,291	8/9/2011	$	20.76	Open Market
RH Fund 1, L.P.	Purchase	5,793	8/9/2011	$	21.27	Open Market
RH Fund 1, L.P.	Purchase	5,359	8/9/2011	$	20.61	Open Market
RH Fund 1, L.P.	Purchase	89,323	8/9/2011	$	21.32	Open Market
RH Fund 1, L.P.	Purchase	33,732	8/9/2011	$	21.26	Open Market
Relational Investors LLC	Purchase	18,594	8/9/2011	$	20.76	Open Market
Relational Investors LLC	Purchase	7,538	8/9/2011	$	21.27	Open Market
Relational Investors LLC	Purchase	6,973	8/9/2011	$	20.61	Open Market
Relational Investors LLC	Purchase	116,218	8/9/2011	$	21.31	Open Market
Relational Investors LLC	Purchase	43,888	8/9/2011	$	21.26	Open Market
RH Fund 6, L.P.	Purchase	8,822	8/9/2011	$	20.76	Open Market
RH Fund 6, L.P.	Purchase	3,576	8/9/2011	$	21.27	Open Market
RH Fund 6, L.P.	Purchase	3,308	8/9/2011	$	20.60	Open Market

RH Fund 6, L.P.	Purchase	55,140	8/9/2011	$	21.31	Open Market
RH Fund 6, L.P.	Purchase	20,823	8/9/2011	$	21.26	Open Market
Relational Investors VIII, L.P.	Purchase	39,101	8/9/2011	$	20.76	Open Market
Relational Investors VIII, L.P.	Purchase	15,858	8/9/2011	$	21.27	Open Market
Relational Investors VIII, L.P.	Purchase	14,669	8/9/2011	$	20.61	Open Market
Relational Investors VIII, L.P.	Purchase	244,324	8/9/2011	$	21.31	Open Market
Relational Investors VIII, L.P.	Purchase	92,272	8/9/2011	$	21.26	Open Market
Relational Investors IX, L.P.	Purchase	12,238	8/9/2011	$	20.76	Open Market
Relational Investors IX, L.P.	Purchase	3,473	8/9/2011	$	21.27	Open Market
Relational Investors IX, L.P.	Purchase	1,488	8/9/2011	$	21.27	Open Market
Relational Investors IX, L.P.	Purchase	3,212	8/9/2011	$	20.60	Open Market
Relational Investors IX, L.P.	Purchase	1,377	8/9/2011	$	20.61	Open Market
Relational Investors IX, L.P.	Purchase	53,542	8/9/2011	$	21.31	Open Market
Relational Investors IX, L.P.	Purchase	22,946	8/9/2011	$	21.31	Open Market
Relational Investors IX, L.P.	Purchase	20,219	8/9/2011	$	21.26	Open Market
Relational Investors IX, L.P.	Purchase	8,666	8/9/2011	$	21.26	Open Market
Relational Investors X, L.P.	Purchase	3,971	8/9/2011	$	20.76	Open Market
Relational Investors X, L.P.	Purchase	1,609	8/9/2011	$	21.27	Open Market
Relational Investors X, L.P.	Purchase	1,489	8/9/2011	$	20.61	Open Market
Relational Investors X, L.P.	Purchase	24,820	8/9/2011	$	21.31	Open Market
Relational Investors X, L.P.	Purchase	9,373	8/9/2011	$	21.26	Open Market
Relational Investors XV, L.P.	Purchase	4,125	8/9/2011	$	20.76	Open Market
Relational Investors XV, L.P.	Purchase	1,672	8/9/2011	$	21.27	Open Market
Relational Investors XV, L.P.	Purchase	1,546	8/9/2011	$	20.60	Open Market
Relational Investors XV, L.P.	Purchase	25,782	8/9/2011	$	21.31	Open Market
Relational Investors XV, L.P.	Purchase	9,736	8/9/2011	$	21.26	Open Market
Relational Investors XVI, L.P.	Purchase	4,061	8/9/2011	$	20.76	Open Market
Relational Investors XVI, L.P.	Purchase	1,646	8/9/2011	$	21.27	Open Market
Relational Investors XVI, L.P.	Purchase	1,523	8/9/2011	$	20.61	Open Market
Relational Investors XVI, L.P.	Purchase	25,383	8/9/2011	$	21.32	Open Market
Relational Investors XVI, L.P.	Purchase	9,585	8/9/2011	$	21.26	Open Market
Relational Investors XX, L.P.	Purchase	3,741	8/9/2011	$	20.76	Open Market
Relational Investors XX, L.P.	Purchase	1,516	8/9/2011	$	21.27	Open Market
Relational Investors XX, L.P.	Purchase	1,402	8/9/2011	$	20.60	Open Market
Relational Investors XX, L.P.	Purchase	23,383	8/9/2011	$	21.32	Open Market
Relational Investors XX, L.P.	Purchase	8,830	8/9/2011	$	21.26	Open Market
Relational Investors XXII, L.P.	Purchase	5,637	8/9/2011	$	20.76	Open Market
Relational Investors XXII, L.P.	Purchase	2,285	8/9/2011	$	21.27	Open Market
Relational Investors XXII, L.P.	Purchase	2,114	8/9/2011	$	20.60	Open Market
Relational Investors XXII, L.P.	Purchase	35,235	8/9/2011	$	21.32	Open Market
Relational Investors XXII, L.P.	Purchase	13,306	8/9/2011	$	21.26	Open Market
Relational Investors XXIII, L.P.	Purchase	5,236	8/9/2011	$	20.76	Open Market
Relational Investors XXIII, L.P.	Purchase	2,123	8/9/2011	$	21.27	Open Market
Relational Investors XXIII, L.P.	Purchase	1,963	8/9/2011	$	20.61	Open Market
Relational Investors XXIII, L.P.	Purchase	32,730	8/9/2011	$	21.31	Open Market
Relational Investors XXIII, L.P.	Purchase	12,360	8/9/2011	$	21.26	Open Market
Relational Investors LLC	Purchase	8,618	8/9/2011	$	20.76	Open Market

Relational Investors LLC	Purchase	1,521	8/9/2011	$	20.76	Open Market
Relational Investors LLC	Purchase	3,493	8/9/2011	$	21.27	Open Market
Relational Investors LLC	Purchase	617	8/9/2011	$	21.27	Open Market
Relational Investors LLC	Purchase	3,232	8/9/2011	$	20.60	Open Market
Relational Investors LLC	Purchase	570	8/9/2011	$	20.60	Open Market
Relational Investors LLC	Purchase	53,865	8/9/2011	$	21.32	Open Market
Relational Investors LLC	Purchase	9,506	8/9/2011	$	21.31	Open Market
Relational Investors LLC	Purchase	20,341	8/9/2011	$	21.26	Open Market
Relational Investors LLC	Purchase	3,590	8/9/2011	$	21.26	Open Market
Relational Coast Partners, L.P.	Purchase	1,662	8/9/2011	$	20.76	Open Market
Relational Coast Partners, L.P.	Purchase	674	8/9/2011	$	21.27	Open Market
Relational Coast Partners, L.P.	Purchase	623	8/9/2011	$	20.61	Open Market
Relational Coast Partners, L.P.	Purchase	10,393	8/9/2011	$	21.32	Open Market
Relational Coast Partners, L.P.	Purchase	3,925	8/9/2011	$	21.26	Open Market
Relational Coast Partners, L.P.	Purchase	215	8/9/2011	$	20.76	Open Market
Relational Coast Partners, L.P.	Purchase	87	8/9/2011	$	21.27	Open Market
Relational Coast Partners, L.P.	Purchase	80	8/9/2011	$	20.60	Open Market
Relational Coast Partners, L.P.	Purchase	1,349	8/9/2011	$	21.32	Open Market
Relational Coast Partners, L.P.	Purchase	509	8/9/2011	$	21.26	Open Market
Relational Fund Partners, L.P.	Purchase	358	8/9/2011	$	20.76	Open Market
Relational Fund Partners, L.P.	Purchase	145	8/9/2011	$	21.27	Open Market
Relational Fund Partners, L.P.	Purchase	134	8/9/2011	$	20.60	Open Market
Relational Fund Partners, L.P.	Purchase	2,239	8/9/2011	$	21.32	Open Market
Relational Fund Partners, L.P.	Purchase	845	8/9/2011	$	21.26	Open Market
Relational Fund Partners, L.P.	Purchase	84	8/9/2011	$	20.76	Open Market
Relational Fund Partners, L.P.	Purchase	34	8/9/2011	$	21.27	Open Market
Relational Fund Partners, L.P.	Purchase	31	8/9/2011	$	20.61	Open Market
Relational Fund Partners, L.P.	Purchase	526	8/9/2011	$	21.31	Open Market
Relational Fund Partners, L.P.	Purchase	198	8/9/2011	$	21.26	Open Market
Relational Fund Partners, L.P.	Purchase	2	8/9/2011	$	20.76	Open Market
Relational Fund Partners, L.P.	Purchase	14	8/9/2011	$	21.31	Open Market
Relational Fund Partners, L.P.	Purchase	5	8/9/2011	$	21.26	Open Market
Relational Investors Alpha Fund I, L.P.	Purchase	9,942	8/9/2011	$	20.76	Open Market
Relational Investors Alpha Fund I, L.P.	Purchase	4,030	8/9/2011	$	21.27	Open Market
Relational Investors Alpha Fund I, L.P.	Purchase	3,728	8/9/2011	$	20.60	Open Market
Relational Investors Alpha Fund I, L.P.	Purchase	62,142	8/9/2011	$	21.31	Open Market
Relational Investors Alpha Fund I, L.P.	Purchase	23,467	8/9/2011	$	21.26	Open Market
Relational Investors LLC	Purchase	24,367	8/9/2011	$	20.76	Open Market
Relational Investors LLC	Purchase	9,878	8/9/2011	$	21.27	Open Market
Relational Investors LLC	Purchase	9,137	8/9/2011	$	20.61	Open Market
Relational Investors LLC	Purchase	152,297	8/9/2011	$	21.32	Open Market
Relational Investors LLC	Purchase	57,513	8/9/2011	$	21.26	Open Market
Relational Investors, L.P.	Purchase	33,415	8/10/2011	$	21.48	Open Market
Relational Investors, L.P.	Purchase	250,614	8/10/2011	$	21.43	Open Market
RH Fund 1, L.P.	Purchase	14,292	8/10/2011	$	21.48	Open Market
RH Fund 1, L.P.	Purchase	107,190	8/10/2011	$	21.43	Open Market
Relational Investors LLC	Purchase	18,595	8/10/2011	$	21.48	Open Market

Relational Investors LLC	Purchase	139,463	8/10/2011	$	21.43	Open Market
RH Fund 6, L.P.	Purchase	8,822	8/10/2011	$	21.48	Open Market
RH Fund 6, L.P.	Purchase	66,169	8/10/2011	$	21.43	Open Market
Relational Investors VIII, L.P.	Purchase	39,095	8/10/2011	$	21.48	Open Market
Relational Investors VIII, L.P.	Purchase	293,154	8/10/2011	$	21.43	Open Market
Relational Investors IX, L.P.	Purchase	12,238	8/10/2011	$	21.48	Open Market
Relational Investors IX, L.P.	Purchase	64,251	8/10/2011	$	21.43	Open Market
Relational Investors IX, L.P.	Purchase	27,536	8/10/2011	$	21.43	Open Market
Relational Investors X, L.P.	Purchase	3,971	8/10/2011	$	21.48	Open Market
Relational Investors X, L.P.	Purchase	29,785	8/10/2011	$	21.43	Open Market
Relational Investors XV, L.P.	Purchase	4,125	8/10/2011	$	21.48	Open Market
Relational Investors XV, L.P.	Purchase	30,941	8/10/2011	$	21.43	Open Market
Relational Investors XVI, L.P.	Purchase	4,061	8/10/2011	$	21.48	Open Market
Relational Investors XVI, L.P.	Purchase	30,462	8/10/2011	$	21.43	Open Market
Relational Investors XX, L.P.	Purchase	3,741	8/10/2011	$	21.48	Open Market
Relational Investors XX, L.P.	Purchase	28,061	8/10/2011	$	21.43	Open Market
Relational Investors XXII, L.P.	Purchase	5,637	8/10/2011	$	21.48	Open Market
Relational Investors XXII, L.P.	Purchase	42,284	8/10/2011	$	21.43	Open Market
Relational Investors XXIII, L.P.	Purchase	5,237	8/10/2011	$	21.48	Open Market
Relational Investors XXIII, L.P.	Purchase	39,278	8/10/2011	$	21.43	Open Market
Relational Investors LLC	Purchase	8,618	8/10/2011	$	21.48	Open Market
Relational Investors LLC	Purchase	1,521	8/10/2011	$	21.48	Open Market
Relational Investors LLC	Purchase	64,639	8/10/2011	$	21.43	Open Market
Relational Investors LLC	Purchase	11,407	8/10/2011	$	21.43	Open Market
Relational Coast Partners, L.P.	Purchase	1,663	8/10/2011	$	21.48	Open Market
Relational Coast Partners, L.P.	Purchase	12,474	8/10/2011	$	21.43	Open Market
Relational Coast Partners, L.P.	Purchase	216	8/10/2011	$	21.48	Open Market
Relational Coast Partners, L.P.	Purchase	1,621	8/10/2011	$	21.43	Open Market
Relational Fund Partners, L.P.	Purchase	358	8/10/2011	$	21.48	Open Market
Relational Fund Partners, L.P.	Purchase	2,689	8/10/2011	$	21.43	Open Market
Relational Fund Partners, L.P.	Purchase	84	8/10/2011	$	21.48	Open Market
Relational Fund Partners, L.P.	Purchase	632	8/10/2011	$	21.43	Open Market
Relational Fund Partners, L.P.	Purchase	2	8/10/2011	$	21.48	Open Market
Relational Fund Partners, L.P.	Purchase	20	8/10/2011	$	21.43	Open Market
Relational Investors Alpha Fund I, L.P.	Purchase	9,942	8/10/2011	$	21.48	Open Market
Relational Investors Alpha Fund I, L.P.	Purchase	74,572	8/10/2011	$	21.43	Open Market
Relational Investors LLC	Purchase	24,367	8/10/2011	$	21.48	Open Market
Relational Investors LLC	Purchase	182,758	8/10/2011	$	21.43	Open Market
Relational Investors, L.P.	Purchase	4,290	8/11/2011	$	21.52	Open Market
RH Fund 1, L.P.	Purchase	1,835	8/11/2011	$	21.53	Open Market
Relational Investors LLC	Purchase	2,387	8/11/2011	$	21.53	Open Market
RH Fund 6, L.P.	Purchase	1,132	8/11/2011	$	21.52	Open Market
Relational Investors VIII, L.P.	Purchase	5,029	8/11/2011	$	21.53	Open Market
Relational Investors IX, L.P.	Purchase	1,100	8/11/2011	$	21.52	Open Market
Relational Investors IX, L.P.	Purchase	471	8/11/2011	$	21.53	Open Market
Relational Investors X, L.P.	Purchase	509	8/11/2011	$	21.53	Open Market
Relational Investors XV, L.P.	Purchase	529	8/11/2011	$	21.53	Open Market

Relational Investors XVI, L.P.	Purchase	521	8/11/2011	$	21.53	Open Market
Relational Investors XX, L.P.	Purchase	480	8/11/2011	$	21.52	Open Market
Relational Investors XXII, L.P.	Purchase	724	8/11/2011	$	21.52	Open Market
Relational Investors XXIII, L.P.	Purchase	672	8/11/2011	$	21.52	Open Market
Relational Investors LLC	Purchase	1,107	8/11/2011	$	21.52	Open Market
Relational Investors LLC	Purchase	195	8/11/2011	$	21.53	Open Market
Relational Coast Partners, L.P.	Purchase	213	8/11/2011	$	21.53	Open Market
Relational Coast Partners, L.P.	Purchase	27	8/11/2011	$	21.53	Open Market
Relational Fund Partners, L.P.	Purchase	46	8/11/2011	$	21.52	Open Market
Relational Fund Partners, L.P.	Purchase	10	8/11/2011	$	21.52	Open Market
Relational Investors Alpha Fund I, L.P.	Purchase	1,276	8/11/2011	$	21.52	Open Market
Relational Investors LLC	Purchase	3,129	8/11/2011	$	21.53	Open Market