SPD Smith of Australia scored his sixth century in the calendar year 2017 when he scored 102 not out in the drawn test against England at Melbourne.  His six centuries are the most scored by a batsman  in the Calendar year 2017. He went past D Elgar of South Africa and V Kohli of India  who had scored five centuries in 2017. The centuries scored by these three batsmen are tabulated below

SPD SMITH OF AUSTRALIA
No	Runs	Inns	Opposition	Ground	Start Date
1	109	3	v India	Pune	23 Feb 2017
2	178*	1	v India	Ranchi	16 Mar 2017
3	111	1	v India	Dharamsala	25 Mar 2017
4	141*	2	v England	Brisbane	23 Nov 2017
5	239	2	v England	Perth	14 Dec 2017
6	102*	3	v England	Melbourne	26 Dec 2017
D ELGAR OF SOUTH AFRICA
No	Runs	Inns	Opposition	Ground	Start Date
1	129	1	v Sri Lanka	Cape Town	02 Jan 2017
2	140	1	v New Zealand	Dunedin	8 Mar 2017
3	136	4	v England	The Oval	27 Jul 2017
4	199	1	v Bangladesh	Potchefstroom	28 Sep 2017
5	113	1	v Bangladesh	Bloemfontein	06 Oct 2017
V KOHLI OF INDIA
No	Runs	Inns	Opposition	Ground	Start Date
1	204	1	v Bangladesh	Hyd-RGS	09 Feb 2017
2	103*	3	v Sri Lanka	Galle	26 Jul 2017
3	104*	3	v Sri Lanka	Kolkata	16 Nov 2017
4	213	2	v Sri Lanka	Nagpur	24 Nov 2017
5	243	1	v Sri Lanka	Delhi	02 Dec 2017

The following table lists the eighteen occasions of a batsman scoring six or more centuries in a calendar year.

No	Player	Team	Mat	Inns	NO	Runs	HS	Ave	Cen	Year
1	Mohd Yousuf	Pak	11	19	1	1788	202	99.33	9	2006
2	IVA Richards	Win	11	19	0	1710	291	90.00	7	1976
3	PA de Silva	Srl	11	19	3	1220	168	76.25	7	1997
4	RT Ponting	Aus	10	18	3	1333	196	88.86	7	2006
5	SR Tendulkar	Ind	14	23	3	1562	214	78.10	7	2010
6	DCS Compton	Eng	9	15	1	1159	208	82.78	6	1947
7	GS Sobers	Win	8	13	4	1299	365*	144.33	6	1958
8	ML Hayden	Aus	11	17	1	1160	197	72.50	6	2002
9	MP Vaughan	Eng	14	26	2	1481	197	61.70	6	2002
10	RT Ponting	Aus	11	18	3	1503	257	100.20	6	2003
11	DR Martyn	Aus	14	26	2	1353	161	56.37	6	2004
12	RT Ponting	Aus	15	28	5	1544	207	67.13	6	2005
13	GC Smith	SAF	15	25	2	1656	232	72.00	6	2008
14	TM Dilshan	Srl	11	18	1	1097	162	64.52	6	2009
15	JH Kallis	SAF	11	19	4	1198	201*	79.86	6	2010
16	DA Warner	Aus	9	18	0	1136	145	63.11	6	2014
17	SPD Smith	Aus	13	24	4	1474	215	73.70	6	2015
18	SPD Smith	Aus	11	20	3	1305	239	76.76	6	2017

SPD Smith’s feat of scoring six centuries in the calendar year 2017 provides the eighth occasion of an Australian batsman accomplishing such a feat. All such occcaions are listed below

No	Player	Team	Mat	Inns	NO	Runs	HS	Ave	Cen	Year
1	RT Ponting	Aus	10	18	3	1333	196	88.86	7	2006
2	ML Hayden	Aus	11	17	1	1160	197	72.50	6	2002
3	RT Ponting	Aus	11	18	3	1503	257	100.20	6	2003
4	DR Martyn	Aus	14	26	2	1353	161	56.37	6	2004
5	RT Ponting	Aus	15	28	5	1544	207	67.13	6	2005
6	DA Warner	Aus	9	18	0	1136	145	63.11	6	2014
7	SPD Smith	Aus	13	24	4	1474	215	73.70	6	2015
8	SPD Smith	Aus	11	20	3	1305	239	76.76	6	2017

RT Ponting and SPD Smith are the two batsmen who have accomplished the feat of scoring six or more centuries in a calendar year on two or more occasions in the annals of test cricket

No	Player	Team	Mat	Inns	NO	Runs	HS	Ave	Cen	Year
1	RT Ponting	Aus	10	18	3	1333	196	88.86	7	2006
2	RT Ponting	Aus	11	18	3	1503	257	100.20	6	2003
3	RT Ponting	Aus	15	28	5	1544	207	67.13	6	2005
1	SPD Smith	Aus	13	24	4	1474	215	73.70	6	2015
2	SPD Smith	Aus	11	20	3	1305	239	76.76	6	2017