Home Run Rate in record setting seasons: 1927, 1961, 1998, 2001.

Top ten in homers in the league sorted by Home Run Rate (AB/HR):

1927

nameFirst	nameLast	yearID	teamID	AB	HR	HRrate	BA	lgID	PA
Babe	Ruth	1927	NYA	540	60	09.0	.356	AL
Lou	Gehrig	1927	NYA	584	47	12.4	.373	AL
Ken	Williams	1927	SLA	423	17	24.9	.322	AL
Al	Simmons	1927	PHA	406	15	27.1	.392	AL
Tony	Lazzeri	1927	NYA	570	18	31.7	.309	AL
Mickey	Cochrane	1927	PHA	432	12	36.0	.338	AL
Harry	Heilmann	1927	DET	505	14	36.1	.398	AL
Marty	McManus	1927	DET	369	9	41.0	.268	AL
Goose	Goslin	1927	WS1	581	13	44.7	.334	AL
Bob	Fothergill	1927	DET	527	9	58.6	.359	AL
Bibb	Falk	1927	CHA	535	9	59.4	.327	AL

1961

nameFirst	nameLast	yearID	teamID	AB	HR	HRrate	BA	lgID	PA
Mickey	Mantle	1961	NYA	514	54	09.5	.317	AL	646
Roger	Maris	1961	NYA	590	61	09.7	.269	AL	698
Jim	Gentile	1961	BAL	486	46	10.6	.302	AL	601
Harmon	Killebrew	1961	MIN	541	46	11.8	.288	AL	656
Rocky	Colavito	1961	DET	583	45	13.0	.290	AL	708
Norm	Cash	1961	DET	535	41	13.0	.361	AL	672
Leon	Wagner	1961	LAA	453	28	16.2	.280	AL	511
Al	Smith	1961	CHA	532	28	19.0	.278	AL	602
Bob	Allison	1961	MIN	556	29	19.2	.245	AL	677
Bill	Skowron	1961	NYA	561	28	20.0	.267	AL	607

1998

nameFirst	nameLast	yearID	teamID	AB	HR	HRrate	BA	lgID	PA
Mark	McGwire	1998	SLN	509	70	07.3	.299	NL	681
Sammy	Sosa	1998	CHN	643	66	09.7	.308	NL	722
Greg	Vaughn	1998	SDN	573	50	11.5	.272	NL	661
Andres	Galarraga	1998	ATL	555	44	12.6	.305	NL	648
Vinny	Castilla	1998	COL	645	46	14.0	.319	NL	697
Javy	Lopez	1998	ATL	489	34	14.4	.284	NL	534
Barry	Bonds	1998	SFN	552	37	14.9	.303	NL	697
Moises	Alou	1998	HOU	584	38	15.4	.312	NL	679
Jeff	Bagwell	1998	HOU	540	34	15.9	.304	NL	661
Jeromy	Burnitz	1998	MIL	609	38	16.0	.263	NL	691
Vladimir	Guerrero	1998	MON	623	38	16.4	.324	NL	677
Chipper	Jones	1998	ATL	601	34	17.7	.313	NL	707

2001

nameFirst	nameLast	yearID	teamID	AB	HR	HRrate	BA	lgID	PA
Barry	Bonds	2001	SFN	476	73	06.5	.328	NL	664
Sammy	Sosa	2001	CHN	577	64	09.0	.328	NL	711
Luis	Gonzalez	2001	ARI	609	57	10.7	.325	NL	728
Todd	Helton	2001	COL	587	49	12.0	.336	NL	696
Shawn	Green	2001	LAN	619	49	12.6	.297	NL	701
Larry	Walker	2001	COL	497	38	13.1	.350	NL	601
Richie	Sexson	2001	MIL	598	45	13.3	.271	NL	667
Phil	Nevin	2001	SDN	546	41	13.3	.306	NL	624
Chipper	Jones	2001	ATL	572	38	15.1	.330	NL	677
Jeff	Bagwell	2001	HOU	600	39	15.4	.288	NL	717

Best HR Rates in each of those four years:
1927: Babe Ruth 9.0 60 HR
1961: Mickey Mantle 9.5 54 HR; Roger Maris 9.7 61 HR
1998: Mark McGwire 7.3 70 HR
2001: Barry Bonds 6.5 73 HR

Rk	Player	HR	AB	Year	Age	Tm	Lg	G	PA	R	H	2B	3B	RBI	BB	IBB	SO	HBP	SH	SF	GDP	SB	CS	BA	OBP	SLG	OPS	Pos
1	Barry Bonds	73	476	2001	36	SFG	NL	153	664	129	156	32	2	137	177	35	93	9	0	2	5	13	3	.328	.515	.863	1.379	*7/DH
2	Mark McGwire	70	509	1998	34	STL	NL	155	681	130	152	21	0	147	162	28	155	6	0	4	8	1	0	.299	.470	.752	1.222	*3/H
3	Sammy Sosa	66	643	1998	29	CHC	NL	159	722	134	198	20	0	158	73	14	171	1	0	5	20	18	9	.308	.377	.647	1.024	*9/8
4	Mark McGwire	65	521	1999	35	STL	NL	153	661	118	145	21	1	147	133	21	141	2	0	5	12	0	0	.278	.424	.697	1.120	*3/H
5	Sammy Sosa	64	577	2001	32	CHC	NL	160	711	146	189	34	5	160	116	37	153	6	0	12	6	0	2	.328	.437	.737	1.174	*9
6	Sammy Sosa	63	625	1999	30	CHC	NL	162	712	114	180	24	2	141	78	8	171	3	0	6	17	7	8	.288	.367	.635	1.002	*98
7	Roger Maris	61	590	1961	26	NYY	AL	161	698	132	159	16	4	141	94	0	67	7	0	7	16	0	0	.269	.372	.620	.993	*98/H
8	Babe Ruth	60	540	1927	32	NYY	AL	151	691	158	192	29	8	165	137		89	0	14			7	6	.356	.486	.772	1.258	*97
9	Babe Ruth	59	540	1921	26	NYY	AL	152	693	177	204	44	16	168	145		81	4	4			17	13	.378	.512	.846	1.359	*78/13
10	Ryan Howard	58	581	2006	26	PHI	NL	159	704	104	182	25	1	149	108	37	181	9	0	6	7	0	0	.313	.425	.659	1.084	*3/H
11	Mark McGwire	58	540	1997	33	TOT	ML	156	657	86	148	27	0	123	101	16	159	9	0	7	9	3	0	.274	.393	.646	1.039	*3/H
12	Hank Greenberg	58	556	1938	27	DET	AL	155	681	143	175	23	4	147	119		92	3	3			7	5	.315	.438	.683	1.122	*3
13	Jimmie Foxx	58	585	1932	24	PHA	AL	154	702	151	213	33	9	169	116		96	0	0			3	7	.364	.469	.749	1.218	*35

Provided by Baseball-Reference.com: View Play Index Tool Used
Generated 4/3/2016.

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