How ICC Rankings Annual Update Works

ICC operates a ranking system to rank men’s teams playing across Test, One-Day International and Twenty20 International formats and women’s teams playing One-Day International and Twenty20 International cricket.

ICC publishes up to date current ranking of teams according to that system on its official portal - ICC Team Rankings

ICC Rankings changes overnight once every year when ICC updates Ranking Points of each team to keep the Rankings current and accurate. The update takes place on 1^st May every year when the ICC ODI Rankings are adjusted according to these predefined rules:

• Any points earned earlier than the last 36 months (since 1 May of 3 years ago) are discarded
• Weightage of all points earned between the last 13 to 36 months (between the May of 3 years ago to April of previous year) is set to 50%
• All points earned during the last 12 months (from May of previous year to April of current year) continue to carry the weightage of 100%

Till 30 April of the next year, the above rules remain in effect. Till the next annual update, points earned by matches played during this period are simply added into the annually updated rankings as on 1^st May to give the current ICC Rankings. That means, on every 30 April of a year:

• Points earned during the previous 24 months (since the May of two years ago) are counted with 100% weightage.
• Points earned in between the previous 25^th and 48^th months (since the April of 2 years ago to May of 4 years ago) are counted with 50% weightage.

The idea of ICC ODI Rankings was to build a mechanism to quantify the success of different teams, benchmark their performance and identify the top, the average and the below par teams at certain point in time. The mechanism works on a combination of performance in a match and the current form of the competing teams.

The official ICC website describes the Rankings in these words: 

A team that, over the period being rated, wins as often as it loses while playing an average mix of strong and weak opponents will have a rating of close to 100. A rating of 100 could also correspond to a side that wins more often than it loses but who has generally played more matches against weak teams. Similarly, if the majority of its matches are against strong teams, then a rating of 100 could be achieved despite having more defeats than victories.

It is quite often the case that there are a number of teams in the 90-110 range. These teams are of broadly similar standard. A rating above 120 suggests consistently strong performances. Above 130 is rarely achieved and suggests a high degree of dominance over all other teams.
Source: icc-cricket.com

For the purposes of quick referencing, ranking of 100 can be considered as par, 120 as excellent and 130 above as exceptional. This piece of information helps a lot in seeing a team’s ranking in the context of its own ranking points instead of judging its performance only on the basis of where it stands in the list of twelve ODI Ranked teams at any point.

Theoretically, a team can come out as the number one ranked team in the world with 110 ranking points as well but in the context of strength of performance, that number one ranked team may fall way behind a number one ranked team with 130 ranking points or even a number two or number three team with 120 points.

The other aspect of ICC ODI Rankings is the recent form of the teams. The idea there is to gage the consistency in performance of a team over a period of time and reduce the impact of occasional spike in the performance of any team. The rankings are designed to judge the teams during a reasonable period rather than on the basis of few good or bad series or matches. For that reason, ICC ODI Rankings includes the performances of last 3 to 4 years as detailed earlier.

On that note, it is also worth having a look at how different teams have performed during recent ICC ODI seasons as it also gives a fair idea of why and how some teams will benefit from the annual update and some teams will lose some points (and ranking position). Having a look at the points earned during specific seasons also indicates the trend of improvement or decline in the recent performance of teams. It clearly answers why certain teams enjoy a high ranking position even after performing badly in recent times whereas some teams are struggling in the lower half of the table even after performing better.