# Defining a Unit

<figure><img src="https://2847533834-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FVy65sax6FVoNo2UTlJ0x%2Fuploads%2FqoiSMv4LgPH0WB0vbUbq%2Fimage.png?alt=media&#x26;token=b813f8e7-d2a8-4e83-9fb6-92ce74f7cbfe" alt="Screenshot of the Unit step of the Variable dialog"><figcaption><p>Unit step of the Variable wizard</p></figcaption></figure>

{% hint style="info" %}
If this is your first time defining a Unit, we recommend reading the [**Introduction to Units**](https://help.taglo.io/units/introduction-to-units) first
{% endhint %}

You will most commonly define [**Units**](https://help.taglo.io/units) as part of the [**Variable wizard**](https://help.taglo.io/variables/variable-basics/unit-and-calculations). You will only need to define a Unit if your Variable is an `Assumptions` Variable, or if you select the `Specify Unit` option for a `Calculation` Variable.

The Unit step is simply a list of [**Unit Parts**](https://help.taglo.io/key-unit-concepts#compound-units), in a standard [**List View**](https://help.taglo.io/using-taglo-software/the-taglo-interface/list-views), in which you can *Add*, *Edit* and *Duplicate* Unit Parts. The resulting Unit is shown as a formula at the top of the step.

Each Unit Part can be edited in a separate wizard, or specific properties can be edited individually by clicking on one of the shortcut buttons displayed.

<details>

<summary>Shortcut buttons (as per above image)</summary>

* <img src="https://2847533834-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FVy65sax6FVoNo2UTlJ0x%2Fuploads%2FxXUWB7PYHNLf5tIDPQSO%2Fimage.png?alt=media&#x26;token=0fd6a507-11fa-421b-913c-3aa7eb2c278d" alt="" data-size="line">Change the base [**Tag**](https://help.taglo.io/tags) and/or [**Unit Factor**](https://help.taglo.io/advanced-units#factors)
* <img src="https://2847533834-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FVy65sax6FVoNo2UTlJ0x%2Fuploads%2FiZ2DBLfhFIwqg74sZsBb%2Fimage.png?alt=media&#x26;token=493dd7f3-485c-4e69-838e-5ad24c364b48" alt="" data-size="line">Change the Order
* <img src="https://2847533834-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FVy65sax6FVoNo2UTlJ0x%2Fuploads%2FZB3NsSZNwd5btBWZ4d8F%2Fimage.png?alt=media&#x26;token=d86fd46b-1675-4d89-b1d2-c9ebe264faf6" alt="" data-size="line">Change the Time Type (`Flow`, `Balance`, `Flow (Constant)`, `Balance (Constant)`
* <img src="https://2847533834-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FVy65sax6FVoNo2UTlJ0x%2Fuploads%2F8lf1qcvwkpF1IQPuRiN3%2Fimage.png?alt=media&#x26;token=5ce65062-d9fd-4f74-b554-05a5f0c16130" alt="" data-size="line">`Change the Time Offset`
* <img src="https://2847533834-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FVy65sax6FVoNo2UTlJ0x%2Fuploads%2FEN2B4zBfArqAPQDUjmfT%2Fimage.png?alt=media&#x26;token=497d866d-62b2-4e7f-995d-06e9486f029e" alt="" data-size="line">`Add a Context modifier`
* <img src="https://2847533834-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FVy65sax6FVoNo2UTlJ0x%2Fuploads%2F82Y86mKV5DzLXBlJoa30%2Fimage.png?alt=media&#x26;token=3c4f76fc-2c58-4251-ad50-7d61f4add2c2" alt="" data-size="line">Multiply the Order by -1
* <img src="https://2847533834-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FVy65sax6FVoNo2UTlJ0x%2Fuploads%2FVHPIXoYXIByxlHUf7Og3%2Fimage.png?alt=media&#x26;token=a70b4c66-fc50-41e3-a5df-3e14994f027e" alt="" data-size="line">Make a copy of the Unit Part

</details>

{% hint style="info" %}
Functionality of the Unit step depends on the context. You will find additional options if your Variable has [**Dimensions**](https://help.taglo.io/dimensions), or if you are creating a [**Data Point**](https://help.taglo.io/assumptions/assumptions-wizard/linking-to-external-data) from scratch.

These differences are covered in the relevant sections of documentation.
{% endhint %}

## Default Unit

You can set a default Unit for new Variables by navigating to [**Model Settings**](https://help.taglo.io/models/model-editor#model-settings)**.**