which rockies rookie had the lowest era in a season with at least 100 ip

Jhoulys Chacin has the lowest ERA by a Rockies rookie with 100.0+ innings pitched, with an ERA of 3.28 in 2010.

	NAME	ERA	IP	SEASON	TM	G	W	L	W%	GS	SO	CG	SHO	H	ER	R	HR	BB	HBP	GF	IBB	TBF	WP	K/9	BB/9	K/BB	HR/9	K%	BB%	WHIP	BABIP	RA	ERA-	FIP	FIP-	H/9	PRAA
1	Jhoulys Chacin J. Chacin	3.28	137.1	2010	COL	28	9	11	.450	21	138	0	0	114	50	64	10	61	9	2	5	583	4	9.04	4.00	2.26	0.66	23.7	10.5	1.27	.285	4.19	72	3.54	84	7.47	10.3
2	Tyler Anderson T. Anderson	3.54	114.1	2016	COL	19	5	6	.455	19	99	0	0	119	45	50	12	28	3	0	2	478	4	7.79	2.20	3.54	0.94	20.7	5.9	1.29	.318	3.94	73	3.58	81	9.37	10.1
3	Denny Stark D. Stark	4.00	128.1	2002	COL	32	11	4	.733	20	64	0	0	108	57	69	25	64	5	1	4	554	2	4.49	4.49	1.00	1.75	11.6	11.6	1.34	.210	4.84	83	6.10	135	7.57	-20.4
4	Armando Reynoso A. Reynoso	4.00	189.0	1993	COL	30	12	11	.522	30	117	4	0	206	84	101	22	63	9	0	7	830	7	5.57	3.00	1.86	1.05	14.1	7.6	1.42	.297	4.81	87	4.40	104	9.81	-3.4
5	Tyler Matzek T. Matzek	4.05	117.2	2014	COL	20	6	11	.353	19	91	1	1	120	53	53	9	44	3	1	1	503	3	6.96	3.37	2.07	0.69	18.1	8.7	1.39	.312	4.05	94	3.77	95	9.18	2.9
6	Kyle Freeland K. Freeland	4.10	156.0	2017	COL	33	11	11	.500	28	107	0	0	169	71	78	17	63	8	0	4	688	1	6.17	3.63	1.70	0.98	15.6	9.2	1.49	.308	4.50	82	4.56	100	9.75	0.6
7	Germán Márquez G. Márquez	4.39	162.0	2017	COL	29	11	7	.611	29	147	0	0	174	79	82	25	49	8	0	3	701	6	8.17	2.72	3.00	1.39	21.0	7.0	1.38	.316	4.56	88	4.40	96	9.67	3.4
8	Jason Jennings J. Jennings	4.52	185.1	2002	COL	32	16	8	.667	32	127	0	0	201	93	102	26	70	8	0	2	808	10	6.17	3.40	1.81	1.26	15.7	8.7	1.46	.303	4.95	93	4.67	103	9.76	-2.1
9	Jon Gray J. Gray	4.61	168.0	2016	COL	29	10	10	.500	29	185	1	1	153	86	92	18	59	12	0	2	712	7	9.91	3.16	3.14	0.96	26.0	8.3	1.26	.308	4.93	95	3.60	82	8.20	14.6
10	Antonio Senzatela A. Senzatela	4.68	134.2	2017	COL	36	10	5	.667	20	102	0	0	128	70	72	18	47	4	3	1	564	1	6.82	3.14	2.17	1.20	18.1	8.3	1.30	.280	4.81	94	4.51	99	8.55	1.2
11	John Thomson J. Thomson	4.71	166.1	1997	COL	27	7	9	.438	27	106	2	1	193	87	94	15	51	5	0	0	721	2	5.74	2.76	2.08	0.81	14.7	7.1	1.47	.327	5.09	91	4.01	85	10.44	12.3
12	Jason Hirsh J. Hirsh	4.81	112.1	2007	COL	19	5	7	.417	19	75	1	0	103	60	63	18	48	2	0	5	483	5	6.01	3.85	1.56	1.44	15.5	9.9	1.34	.250	5.05	101	5.31	114	8.25	-7.6
13	Shawn Chacon S. Chacon	5.06	160.0	2001	COL	27	6	10	.375	27	134	0	0	157	90	96	26	87	10	0	10	711	6	7.54	4.89	1.54	1.46	18.8	12.2	1.53	.289	5.40	97	5.30	110	8.83	-6.8
14	Bobby Jones B. Jones	5.22	141.1	1998	COL	35	7	8	.467	20	109	1	0	153	82	87	12	66	6	1	0	630	4	6.94	4.20	1.65	0.76	17.3	10.5	1.55	.323	5.54	100	4.22	88	9.74	8.5
15	Jeff Francis J. Francis	5.68	183.2	2005	COL	33	14	12	.538	33	128	0	0	228	116	119	26	70	8	0	5	828	2	6.27	3.43	1.83	1.27	15.5	8.5	1.62	.339	5.83	122	4.73	106	11.17	-4.9
16	Aaron Cook A. Cook	6.02	124.0	2003	COL	43	4	6	.400	16	43	1	0	160	83	89	8	57	8	4	7	579	10	3.12	4.14	0.75	0.58	7.4	9.8	1.75	.328	6.46	122	4.74	102	11.61	-1