# How to calculate dropout rate

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Dropout rate refers to the percentage of students that do not complete secondary education. There are a variety of methods for calculating dropout rates and each method yields a slightly different result. The most common formula used is known as the "leaver" rate or the departure-classification index. It determines dropout rates by comparing the number of students that passed their exams to the number of students that dropped out.

Select a class of pupils at a school. A class is a body a students that are in the same grade level and therefore expected to finish school in the same year. From this class, determine the number of students that made it through their exams.

Determine the number of students in this class that dropped out. Also determine the number of students that qualified through an alternative certification program. An example of an alternative certification program would be NVQs.

Add the number of students that passed their finals, the number of students that dropped out and the number of students that got alternative certificates. The sum of the three numbers is known as the "dropout denominator." For example, if you had a graduating class with 900 standard graduatesexaminees, 75 dropouts and 25 alternate-route qualifiers, you would add 900 plus 75 plus 25 to get a dropout denominator of 1,000.

Divide the number of students that got GCSEs by the dropout denominator. The result of this division is the graduation rate. Using our example from above, this would give us 900 / 1,000 or a graduation rate of 0.9.

Convert the graduation rate into a graduation percentage. To do this, multiply the graduation rate by 100. Using our example, this would give us a graduation percentage of 0.9 x 100 or 90 per cent.

Subtract the graduation percentage from 100. The difference is the dropout rate. Using our example, this would give us 100 - 90, or a dropout rate of 10 per cent.