---
title: "Label values and metric values"
slug: "label-values-and-metric-values"
tags: ["property type", "label value", "metric value", "unit scheme", "currencyAndAmount", "Basic", "NoUnits", "Iso4127Currency"]
updated: 2024-08-30T14:33:12Z
published: 2024-08-30T14:33:12Z
canonical: "support.lusid.com/label-values-and-metric-values"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://support.lusid.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Label values and metric values

When you attach a single-value property to an entity you must create it as either a *label value* or a *metric value*. This is determined by the underlying data type of the property type.

When you [create a property type](/v1/docs/how-do-i-create-a-property-type), you specify a data type that can either be:

- A primitive built-in data type such as `string`, `number`, `boolean` or `date`.
- A [complex built-in data type](/v1/docs/what-is-a-data-type) such as `rating` or `currencyAndAmount`.
- A [custom data type](/v1/docs/how-do-i-create-a-derived-property-type) you create yourself.

Each data type has an underlying value type that automatically determines whether property values must be created as label values or [metric values](/v1/docs/label-values-and-metric-values#creating-a-property-type-that-mandates-metric-values).

## Creating a property type that mandates label values

The following property type request uses the built-in complex data type `rating`:

```json
curl -X POST "https://<your-domain>.lusid.com/api/api/propertydefinitions"
  -H "Authorization: Bearer <your-API-access-token>"
  -H "Content-Type: application/json-patch+json"
  -d '{
   "domain": "Instrument",
   "scope": "BBG",
   "code": "AnalystRating",
   "displayName": "Analyst Rating",
   "dataTypeId": {"scope": "system", "code": "rating"},
   "lifeTime": "TimeVariant",
   "constraintStyle": "Property",
   "propertyDescription": "Analyst ratings from Bloomberg for instruments"
  }'
```

In the response, LUSID confirms that property values must be [created as label values](/v1/docs/how-do-i-add-a-property-to-an-entity#creating-a-property-value-as-a-label-value):

```json
{
  "key": "Instrument/BBG/AnalystRating",
  "valueType": "String",
  "displayName": "Analyst Rating",
  "dataTypeId": {
    "scope": "system",
    "code": "rating"
  },
  "type": "Label",
  "unitSchema": "NoUnits",
  "domain": "Instrument",
  "scope": "BBG",
  "code": "AnalystRating",
  "valueRequired": false,
  "lifeTime": "TimeVariant",
  "constraintStyle": "Property",
  "propertyDefinitionType": "ValueProperty",
  "propertyDescription": "Analyst ratings from Bloomberg for instruments",
   ...
}
```

## Creating a property type that mandates metric values

The following property type request uses the built-in complex data type `currencyAndAmount`:

```json
curl -X POST "https://<your-domain>.lusid.com/api/api/propertydefinitions"
  -H "Authorization: Bearer <your-API-access-token>"
  -H "Content-Type: application/json-patch+json"
  -d '{
   "domain": "Transaction",
   "scope": "Ibor",
   "code": "Fee",
   "displayName": "Broker fee",
   "dataTypeId": {"scope": "system", "code": "currencyAndAmount"},
   "lifeTime": "Perpetual",
   "constraintStyle": "Property",
   "propertyDescription": "Fee paid to broker"
}'
```

In the response, LUSID confirms that property values must be [created as metric values](/v1/docs/how-do-i-add-a-property-to-an-entity#creating-a-property-value-as-a-metric-value), and in addition specifies a unit schema of `Iso4217Currency`:

```json
{
  "key": "Transaction/Ibor/Fee",
  "valueType": "Decimal",
  "displayName": "Broker fee",
  "dataTypeId": {
    "scope": "system",
    "code": "currencyAndAmount"
  },
  "type": "Metric",
  "unitSchema": "Iso4217Currency",
  "domain": "Transaction",
  "scope": "Ibor",
  "code": "Fee",
  "valueRequired": false,
  "lifeTime": "Perpetual",
  "constraintStyle": "Property",
  "propertyDefinitionType": "ValueProperty",
  "propertyDescription": "Fee paid to broker",
  ...
}
```

The `Iso4217Currency` unit schema mandates that when you attach a property to an entity the `metricValue` object must have a `unit` that is a valid ISO 4127 country code specified as a string, for example:

```json
"properties": {
  "Transaction/Ibor/Fee": {
    "key": "Transaction/Ibor/Fee",
    "value": {
      "metricValue": {
        "value": 30,
        "unit": "GBP"
      }
    }
  }
}
```

Note it is possible for a metric value to have a unit schema of `Basic` or `NoUnits`, in which case there is no need to specify a `unit` for a `metricValue` object; it can be left empty or omitted:

```json
"properties": [
  {
    "key": "Instrument/Ibor/ReplacementCost",
    "value": {
      "metricValue": {
        "value": 15,
        "unit": ""
      }
    }
  }
]
```