# Net attendance rate

## Definition

Total number of students in the theoretical age group for a given level of education attending that level at any time during the reference academic year, expressed as a percentage of the total population in that age group.

## Calculation method

Divide the number of students attending a given level of education regardless of age by the population of the age group which officially corresponds to the given level of education, and multiply the result by 100.

## Data required

Data from household surveys on school attendance for a given level of education.

## Data source

Data come from household surveys such as the Demographic and Health Surveys (DHS) and the Multiple Indicator Cluster Surveys (MICS). In a small number of cases, other survey programs are used. For Brazil, household survey-based indicators are calculated from the Pesquisa Nacional por Amostra de Domicílios (PNAD).

## Interpretation

A high NAR denotes a high degree of coverage for the official school-age population. The theoretical maximum value is 100%. Increasing trends can be considered as reflecting improved coverage at the specified level of education. When the NAR is compared with the gross attendance rate (GAR), the difference between the two highlights the incidence of under-aged and over-aged attendance. If the NAR is below 100%, then the complement, i.e. the difference with 100%, provides a measure of the proportion of children not attending at the age for the specified level of education. However, since some of these children/youth could be attending other levels of education, this difference should in no way be considered as indicating the percentage of students not attending. To measure universal primary education, for example, the adjusted primary NAR is calculated on the basis of the percentage of children in the official primary school age range who are attending either primary or secondary education.

## Limitations

As other net rates, the NAR is affected by the use of different reference points for age for attendance and the population.Treatment of missing data. All observations with missing information on age, whether the child is currently attending school, and the current education level attended, are omitted from the calculation of education indicators.

## Purpose

School participation in household surveys and population censuses is commonly measured by whether pupils or students attended a given grade or level of education during the academic reference year. Therefore, indicators of school participation derived from household survey data refer to attendance. An out-of-school child is a child who did not attend formal primary or secondary school during the reference academic year.

## Quality standards

ISCED recalculation of household survey data for education indicators. The age ranges associated with the education levels are based on the International Standard Classification of Education (ISCED). The education levels and grades used in the calculation of education indicators are consistent with each country’s ISCED mapping. Age data methodology. The data collection period for international household survey programmes like the DHS and MICS may not be aligned with the academic year. This can create distortions in the age data used to calculate education indicators. Education systems generally define the intended or “official” ages for a given level of education based on the age of the child at the beginning of the academic year. In other words, the reference date for ages is the start month of the academic year.By contrast, household surveys may collect data on the educational status and age of children many months after the start of the school year. The reference date for age information is the date the survey data were collected, which means it varies among households. Considering the gap between the start of the school year for which attendance data are collected and the date on which the survey was carried out is crucial for accurate calculation of education indicators. To minimize the associated error, the UIS takes different measures depending on the number of months between the start of the academic reference year and the time of survey data collection. • Where information is available on the birth month and year of school-age children, age data are recoded to the age at the start of the academic reference year.• If only the age in years is available, and data for the majority of observations were collected 6 or more months after the start of the school year, one full year is subtracted from the age recorded during data collection (adjusted age = recorded age – 1). For example, if the school year starts on 1 September and data for the majority of observations were collected in March of the following year or later, the ages will be adjusted.• If only the age in years is available, and data for the majority of observations were collected 5 months or less after the start of the school year, age data are used as recorded. For example, if the school year starts on 1 September and data for the majority of observations were collected during the period up to February of the following year, the recorded ages are used without adjustment.

## Types of disaggregation

Data from household surveys are usually disaggregated by sex, location and household wealth quintile. The location (urban or rural) is defined according to national standards, which may differ across countries. Household wealth quintiles are usually determined with the help of an asset index, calculated from assets owned by individual households (housing material, water and sanitation, appliances, vehicles, livestock, etc.).