ICC T20I Championship

ICC T20I Championship

153px ICC T20 Championship logo
Administrator	International Cricket Council
Format	Twenty20 International
First tournament	2007
Last tournament	ongoing
Tournament format	notional (ongoing points accumulation through all matches played)
Number of teams	17
Current champion	New Zealand (132 rating)
Most successful	Sri Lanka (35 months)

The ICC T20 Championship is an international Twenty20 cricket competition run by the International Cricket Council. The competition is notional in that it is simply a ranking scheme overlaid on the regular T20I match schedule. After every T20I match, the two teams involved receive points based on a mathematical formula. The total of each team's points total is divided by the total number of matches to give a rating, and all teams are ranked on a table in order of rating.

Currently, New Zealand leads the ICC T20I Championship.

Qualification

According to the ICC website, "Only teams who have completed at least eight T20 international matches since 1st August between three and four years ago will have their rating above converted into a ranking on the main table."

Points calculations

Time period

Each team scores points based on the results of their matches over the last 3−4 years − all matches played in the 12–24 months since the May before last, plus all the matches played in the 24 months before that, for which the matches played and points earned both count half. Each May, the matches and points earned between 3 and 4 years ago are removed, and the matches and points earned between 1 and 2 years ago switch from 100% weighting to 50% weighting. For example, at May 2014, the matches played between May 2010 and May 2011 were removed, and the matches played between May 2012 and May 2013 switched to 50% weighting. This happens overnight, so can result in teams changing positions in the ranking table despite not playing. ICC Test Championship weightings

Find the points earned from a match

Each time two teams play another match, the rankings table is updated as follows, based on the ratings of the teams immediately before they played. To determine the teams' new ratings after a particular match, first calculate the points earned from the match:

If the gap between the ratings of the two teams before the match was less than 40 points, then:

Match result	Points earned
Win	Opponent's rating + 50
Tie	Opponent's rating
Lose	Opponent's rating − 50

If the gap between the ratings of the two teams before the match was at least 40 points, then:

Match result	Points earned
Stronger team wins	Own rating + 10
Weaker team loses	Own rating − 10
Stronger team ties	Own rating − 40
Weaker team ties	Own rating + 40
Stronger team loses	Own rating − 90
Weaker team wins	Own rating + 90

Example

Suppose Team A, with an initial rating of 100, plays Team B. The table shows the points awarded to the two teams for 9 different initial ratings for B (ranging from 20 to 160), and the three possible match results.

Initial ratings		Scenario	Team A wins & Team B loses. Points earned:				Match tied. Points earned:				Team A loses & Team B wins. Points earned:					Total initial ratings	Total points earned (All 3 results)
Team A	Team B		Team A		Team B		Team A		Team B		Team A		Team B
100	20	Initial ratings at least 40 points apart	Stronger team wins: Own rating + 10	110	Weaker team loses: Own rating − 10	10	Stronger team ties: Own rating − 40	60	Weaker team ties: Own rating + 40	60	Stronger team loses: Own rating − 90	10	Weaker team wins: Own rating + 90	110		120	120
100	40			110		30		60		80		10		130		140	140
100	60			110		50		60		100		10		150		160	160
100	70	Initial ratings less than 40 points apart	Win: Opponent's rating + 50	120	Lose: Opponent's rating − 50	50	Tie: Opponent's rating	70	Tie: Opponent's rating	100	Lose: Opponent's rating − 50	20	Win: Opponent's rating + 50	150		170	170
100	90			140		50		90		100		40		150		190	190
100	110			160		50		110		100		60		150		210	210
100	130			180		50		130		100		80		150		230	230
100	140	Initial ratings at least 40 points apart	Weaker team wins: Own rating + 90	190	Stronger team loses: Own rating − 90	50	Weaker team ties: Own rating + 40	140	Stronger team ties: Own rating − 40	100	Weaker team loses: Own rating − 10	90	Stronger team wins: Own rating + 10	150		240	240
100	160			190		70		140		120		90		170		260	260

This illustrates that:

• The winning team earns more points than the losing team. (Unless the ratings are more than 180 apart and the weaker team wins − highly unlikely.)
• Winning always earns a team 100 points more than losing, and 50 more than tieing.
• The total points earned by the two teams is always the same as the total initial ratings of the two teams.
• The points earned by a winning team increases as the initial rating (quality) of the opposition increases, within the constraints of earning at least its own initial rating + 10, and no more than its own initial rating + 90. A winning team therefore always earns more points than its initial rating, increasing its overall average rating.
• The points earned by a losing team increases as the initial rating (quality) of the opposition increases, within the constraints of earning at least its own initial rating − 90, and no more than its own initial rating − 10. A losing team therefore always earns fewer points than its initial rating, decreasing its overall average rating.
• In a tie, the weaker team usually earns more points than the stronger team (unless the initial ratings are at least 80 apart), reflecting the fact that a tie is a better result for the weaker team than the stronger team. Also, the stronger team will earn fewer points than its initial rating, decreasing its average, and the weaker team more points that its initial rating, increasing its average.
• For a given result, the rule of how the two teams' points are calculated changes as the initial ratings change, from being based on teams' own ratings when one team is far stronger, to being based on the opponent's ratings when the teams are closely matched, back to being based on own ratings when the other team is far stronger. However, despite these sudden changes in the rule, the number of points awarded for each result changes smoothly as the initial ratings change.

Find the new ratings

• Each team's rating is equal to its total points scored divided by the total matches played. (Series are not significant in these calculations).
• Add the match points scored to the points already scored (in previous matches as reflected by the table), add one to the number of matches played, and determine the new rating.
• Points earned by teams depend on the opponent's ratings, therefore this system needed to assign base ratings to teams when it started.

Current rankings

ICC T20I Championship
Rank	Team	Matches	Points	Rating
1	New Zealand	20	2635	132
2	India	22	2894	132
3	West Indies	18	2192	122
4	South Africa	23	2734	119
5	England	20	2279	114
6	Australia	19	2099	110
7	Pakistan	28	2924	104
8	Sri Lanka	25	2444	98
9	Afghanistan	22	1725	78
10	Bangladesh	23	1708	74
11	Netherlands	10	667	67
12	Zimbabwe	19	1105	58
13	Scotland	11	622	57
14	United Arab Emirates	14	757	54
15	Ireland	11	526	48
16	Oman	12	442	37
17	Hong Kong	15	440	29
Insufficient matches
	Papua New Guinea	5	—	44
Reference: ICC Rankings, 4 May 2016
"Matches" is the number of matches played in the 12-24 months since the May before last, plus half the number in the 24 months before that.

Historical ICC T20I Champions

This table lists the teams that have successively held the highest rating since the T20I ranking was introduced.

Country	Start	End	Duration	Cumulative	Highest Rating
England	24 October 2011	8 August 2012	9 months	9 months	140
South Africa	8 August 2012	11 September 2012	1 month	1 month	137
England	12 September 2011	21 September 2012	10 days	10 months	130
South Africa	22 September 2012	28 September 2012	7 days	1 month	134
Sri Lanka	29 September 2012	28 March 2014	18 months	18 months	134
India	28 March 2014	3 April 2014	6 days	6 days	130
Sri Lanka	3 April 2014	4 April 2014	1 day	18 months	131
India	4 April 2014	6 April 2014	2 days	8 days	132
Sri Lanka	6 April 2014	1 May 2014	1 month	19 months	133
India	1 May 2014	7 September 2014	4 months	4 months	131
Sri Lanka	7 September 2014	10 January 2016	16 months	35 months	135
West Indies	10 January 2016	31 January 2016	21 days	21 days	118
India	31 January 2016	9 February 2016	9 days	5 months	120
Sri Lanka	9 February 2016	12 February 2016	3 days	35 months	121
India	12 February 2016	3 May 2016	2.5 months	8 months	127
New Zealand	4 May 2016	Current			132

See also

• ICC Test Championship
• ICC ODI Championship
• International structure of cricket
• ICC Women's Rankings
• ICC Player Rankings

External links

• ICC Test, ODI and T20I Championship Rankings