# Sectors
ESDL allows you to describe a list of sectors that can be used inside your model. In the model you can make a reference to a specific sector in the list from every asset, service, or party. Tools can then calculate total energy consumption per sector, or total investment costs per sector.
The `Sectors` class is a collection of the class `Sector`. The `Sector` class can have the following parameters:
* an `id` paramater that is used for referring to sectors.
* a `name` parameter to describe the name of the sector.
* a `description` parameter to give a description of the sector.
* a `code` parameter to describe the code of the sector.
* a `dataSource` parameter to document the origin of the information you're using
This class is based on the [standaard bedrijfsindeling](https://www.cbs.nl/-/media/_pdf/2018/17/sbi-2008-versie-2018.pdf) as published by CBS:
An example ESDL file with this information looks like:
```markup
```
---
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