# Creating/Referencing Assumptions

## Creating Assumptions from Variables

The easiest way to create new Assumptions, is from the [**Time Segments**](https://help.taglo.io/variables/time-segments) of a [**Variable**](https://help.taglo.io/variables).

Any Time Segment of [**formula type**](https://help.taglo.io/variables/time-segments/time-segment-setup#formula) `Assumptions` will show you how many Assumptions are required for that Time Segment, how many have been selected, and how many are valid.

You will see these indicators in the Time Segment like in the screenshot below.

<figure><img src="https://2847533834-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FVy65sax6FVoNo2UTlJ0x%2Fuploads%2FRmy5gQR14ZEHiOBkoKE6%2Fimage.png?alt=media&#x26;token=9914ead7-c99d-4773-b5a5-f8d713ce3094" alt=""><figcaption><p>A Time Segment with six valid Assumptions</p></figcaption></figure>

When a Time Segment does not have correctly selected Assumptions it will show you a warning, and you will have two options:

1. Use the **Create Missing Assumptions** shortcut (the fastest method)
2. Edit the Time Segment manually

### Create Missing Assumptions shortcut

<figure><img src="https://2847533834-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FVy65sax6FVoNo2UTlJ0x%2Fuploads%2F5WLud52T8zmL02B6dZ3v%2Fimage.png?alt=media&#x26;token=1ab6d9f8-a49e-4ac0-ade4-e86b8ccbf3aa" alt=""><figcaption><p>Time Segment with six missing Assumptions</p></figcaption></figure>

Any Time Segment with missing assumptions will show a **Create Missing Assumptions** <img src="https://2847533834-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FVy65sax6FVoNo2UTlJ0x%2Fuploads%2Fr7ITOSHtZ0ZcMOme4hi2%2Fimage.png?alt=media&#x26;token=c27f2756-bc8b-4adf-9af6-d5a31d14906b" alt="" data-size="line">button, as shown in the screenshot above.

{% hint style="info" %}
In the above example, our Variable has two [**Dimensions**](https://help.taglo.io/dimensions) applied, with a total of 6 line items, and the [**Unit**](https://help.taglo.io/units) is of [`Constant` **Time Type**](https://help.taglo.io/units/key-unit-concepts#constants), meaning that only one Assumption is required for each item.
{% endhint %}

Pressing **Create Missing Assumptions** will bring up an [**Assumption value entry wizard**](https://help.taglo.io/assumptions/assumptions-wizard/assumption-values-step), in which you can directly enter values. After entering the values and pressing **Finish**, an Assumption will be created for each value and added to the Time Segment.

### Time Segment Editing

You can also Edit the Time Segment directly, in the Time Segment step of the Variable wizard, as in the screenshot below (1).

<figure><img src="https://2847533834-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FVy65sax6FVoNo2UTlJ0x%2Fuploads%2FCGk5Jos8ppJAPLAmgHzN%2Fimage.png?alt=media&#x26;token=723db9ec-2792-4347-b4e5-36007a6bf4f7" alt=""><figcaption><p>Edit Time Segment directly</p></figcaption></figure>

In the **Formula** step of the Time Segment dialog, you can select existing Assumptions for the Time Segment if they have already been created, or create new ones, as per the steps shown in the screenshot below:

1. Use the **Item Status** grid <mark style="color:green;">**(1)**</mark> to select the items that you want to create assumptions for - by default, all items are selected (selected items are indicated by the filter <img src="https://2847533834-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FVy65sax6FVoNo2UTlJ0x%2Fuploads%2FxOjJlbzD8SrjTdqNziKE%2Fimage.png?alt=media&#x26;token=d221bcc0-0b5b-4380-ba9d-2684e1f94d32" alt="" data-size="line"> symbol)
2. Press the **New**<img src="https://2847533834-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FVy65sax6FVoNo2UTlJ0x%2Fuploads%2FiwsdorlAJKuPo48syzs0%2Fimage.png?alt=media&#x26;token=bd14fb53-faeb-4acc-b58f-fe4d91dadf30" alt="" data-size="line"> button <mark style="color:green;">**(2)**</mark>, which will bring up an **Assumptions wizard**, in which you can enter values for the new Assumptions
3. On finishing the Assumptions dialog you will see the newly created Assumptions in the Time Segment wizard <mark style="color:green;">**(3)**</mark>. The Item Status grid <mark style="color:green;">**(4)**</mark> will now show a green background for each item, indicating that a matching Assumption is available.
4. **Select** the newly created Assumptions in the Assumptions list <mark style="color:green;">**(3)**</mark>, and note that each item in the Item Status Grid <mark style="color:green;">**(4)**</mark> now has a tick to indicate that an item has been selected.
5. Click finish

<figure><img src="https://2847533834-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FVy65sax6FVoNo2UTlJ0x%2Fuploads%2FskDq0H0zxhZxIA5ljUvE%2Fimage.png?alt=media&#x26;token=ddb027ff-1301-429b-9f9a-95c2818a753b" alt="Screenshots showing the process of creating and selecting assumptions in the Time Segment wizard"><figcaption><p>Adding Assumptions in the Formula step of the Time Segment wizard</p></figcaption></figure>

## Creating standalone Assumptions

You can create Assumptions without an associated Variable. To do this, go to the **Assumptions** Tab of the Model Editor, and open a [**new Assumptions wizard**](https://help.taglo.io/using-taglo-software/the-taglo-interface/adding-items).

Read on to learn more about the Assumptions Wizard.