The Report page has 3 sections:
The Completion metric represents how much of the deck you have studied. For the completion to reach 100% you must study all the cards in the deck at least once.
Retention measures how well you have memorized your deck. It is calculated based on the score you achieved in each session and the number of cards you have studied.
For example, suppose your deck has 10 cards and the first time you study it, you flip 4 cards and get all of them correct. Your score for that session is 100%, but your overall retention is only 40%, since you haven't studied all the cards yet (100% score x 40% completion).
Now, let's say that the next time you study the same 4 cards, you get two of them correct and the other two wrong. Your score is 50% (2 out of 4 correct) and your retention is 20% (50% score x 40% completion). Your new overall retention drops to 30% (the average of the 2 sessions).
Retention is calculated over the last 3 sessions, so it becomes more accurate the more you study.
<aside> 🦊 To get a perfect retention of 100% you must study all your cards and have a perfect score in all of them 3 times in a row.
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A positive trend (indicated by a green icon) means that your retention is improving over time.
A negative trend (indicated by a red icon) means that retention is decreasing over time.
If you see a null trend (indicated by a grey-ish icon with a slash), it is because there are not enough data points yet to calculate the trend or it is not statistically significant.
<aside> ☝🏽 In case you're interested, we use the Pearson correlation coefficient to calculate the trend.
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This chart shows your best score of each day. So, if you studied the same deck 3 times in the same day you will see only one bar for that day, representing the highest of the 3 scores.
<aside> 🔑 If you study a deck multiple times in one day, only the best result will be displayed in the chart for that day.
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Below the chart you can see how many times in the period selected you studied the deck and how many cards you studied. So, if your deck has 10 cards and you studied all of them 3 times the number of cards studied will be 30.