# `BasisPoints`

A count of hundredths of a percent: 25 basis points is 0.25%.

Use it for rate moves and fees in finance, where people talk in basis points. For an ordinary percentage, use [`Percentage`](/docs/types/type-percentage.md).

## Shape

One whole number from -9007199254740991 to 9007199254740991.

## Example

```jadpo
BasisPoints(25)
```

`BasisPoints(number)` checks the number, and one outside its limits breaks `min` or `max`.

`text.parse(raw, as: BasisPoints)` reads one from text that comes from outside. Text that isn't one at all fails `malformed`, such as `25bp`, `25 bp` or `0.25%`.

## Good to know

- It is a whole number and can be below zero. In JSON it is a plain number.
- `==` tells you whether two are the same, and `<` and `list.sort_by` compare and sort them.

## In JSON

A number, in a request, a response or `json.write`:

```json
-25
0
25
```

## Details

<details>
<summary>Text form, storage, how it is shown, and operations</summary>

`BasisPoints` is in the group Money and banking, and has been in Jadpo since 0.1.0.

### Text form

`text.from` writes one standard text form, the same form `text.parse` reads back: `-25`, `0` and `25`.

### How it is stored

It is stored in one column named for the field, of type `bigint`. `25` is stored as `25`.

### How it is shown to people

`text.format(value, locale:)` shows it to people in their locale.

With `locale: Locale.en_gb`:

| Value | Shown |
|---|---|
| `-25` | `-25 bp` |
| `0` | `0 bp` |
| `25` | `25 bp` |
| `1500` | `1,500 bp` |

### Operations

It also takes `text.parse`, `text.from`, `text.format`, `json.read`, `json.write` and `==`. [How every standard type behaves](/docs/every-standard-type-meets-one-contract.md) says how they work.

</details>