# Detailed explanation[Link]

## Score[Link]

For outbound and inbound transactions, we calculate a score by dividing the number of outgoing transactions by the number of incoming transactions for a specific quarter. So the score formula for transactions is (number of deletes + number of outgoing transfers) / (number of creates + number of incoming transfers). The lower the score, the better (more incoming business than outgoing business).

In the score chart you can see the scores of each registrar. Your own score is indicated by a red dot. The scores of other registrars are indicated by a blue dot. Registrars (dots) to the left, have a better score than registrars to the right.

Scores also fall within certain ranges that correspond to a star rating. See the stars in the chart and the dashed vertical lines (the range boundaries). For instance, if a two star rating has a lower bound of 2 and an upper bound of 4, and your score is 3, you are a two star registrar for transactions. In the future, this rating could be directly linked to incentives and/or penalties.

You can read in the next chapter how we calculated the range boundaries for each rating.

### Range boundaries[Link]

The range boundaries of a score define the rating of a registrar and hence define the incentives and/or penalties in the future. In general, range boundaries do not change frequently so that registrars can compare their ratings over time. The range boundaries of the out vs. in score is based on the total number of inbound and outbound transactions in 2018.

The boundary between 1 and 2 stars (which can be seen as the average) is defined by the total number of outbound transactions for all registrars in 2018 divided by the total inbound transactions for all registrars in 2018. This is also called the baseline score. Remark that we use the same formula as the score calculation for an individual registrar. For example, if 2018 would have counted 200.000 create transactions, 180.000 delete transactions, 50.000 inbound and 50.000 outbound transfers (total inbound transfers is equal to total outbound transfers is equal to total transfers), then the boundary between 1 and 2 stars would be equal to (150.000 + 50.000) / (200.000 + 50.000) = 0,8.

The lower boundary is zero, the upper boundary is infinite. The other boundaries are calculated from the boundary between 2 and 3 stars:

The boundary between 2 and 3 stars is half of the boundary between 1 and 2 stars. In our example, this would be 0,8 / 2 = 0,4.

The boundary between 0 and 1 star is one and a half times the boundary between 1 and 2 stars. In our example, this would be 0,8 * 3/2 = 1,2