---
title: "Trend | Grafana k6 documentation"
description: "Trend is an object for representing a custom metric that allows for calculating different statistics on the added values (min, max, average or percentiles)"
---

# Trend

*Trend* is an object for representing a custom metric that allows for calculating different statistics on the added values (min, max, average or percentiles). It’s one of the four [metric types](/docs/k6/latest/javascript-api/k6-metrics/).

Expand table

| Parameter | Type    | Description                                                                                         |
|-----------|---------|-----------------------------------------------------------------------------------------------------|
| `name`    | string  | The name of the custom metric.                                                                      |
| `isTime`  | boolean | A boolean indicating whether the values added to the metric are time values or just untyped values. |

Expand table

| Method                                                                                   | Description                      |
|------------------------------------------------------------------------------------------|----------------------------------|
| [Trend.add(value, \[tags\])](/docs/k6/latest/javascript-api/k6-metrics/trend/trend-add/) | Add a value to the trend metric. |

## Trend usage in Thresholds

When `Trend` is used in a [threshold expression](/docs/k6/latest/using-k6/thresholds/), there are a range of variables that can be used.

- `avg` for average
- `min` for minimum
- `max` for maximum
- `med` for median
- `p(N)` for specific percentile. `N` is a number between `0.0` and `100.0` meaning the percentile value to look at, e.g. `p(99.99)` means the 99.99th percentile.

The unit of these variables and functions are all in milliseconds.

### Example threshold expressions:

- `p(95) < 400` // 95% of requests must finish below 400ms
- `p(99) < 1000` // 99% of requests must finish within 1s.
- `p(50) < 200` // half of requests must finish within 200ms.
- `max < 3000` // the slowest request must finish within 3s.

> #### ⚠️ Don’t use `min` and `max` in thresholds
> 
> We don’t recommend using `min` and `max` for specifying thresholds because these values represent outliers. Use percentiles instead.

### Examples

JavaScript ![Copy code to clipboard](/media/images/icons/icon-copy-small-2.svg) Copy

```javascript
import { Trend } from 'k6/metrics';

const myTrend = new Trend('my_trend');

export default function () {
  myTrend.add(1);
  myTrend.add(2, { tag1: 'value', tag2: 'value2' });
}
```

JavaScript ![Copy code to clipboard](/media/images/icons/icon-copy-small-2.svg) Copy

```javascript
import { Trend } from 'k6/metrics';
import { sleep } from 'k6';
import http from 'k6/http';

const serverWaitingTimeOnLogin = new Trend('serverWaitingTimeOnLogin', true);

export const options = {
  vus: 1,
  duration: '1m',
  thresholds: {
    serverWaitingTimeOnLogin: ['p(95) < 200'],
  },
};

export default function () {
  const resp = http.post('https://quickpizza.grafana.com/api/users/token/login', {
    username: 'default',
    password: 'supersecure',
  });

  serverWaitingTimeOnLogin.add(resp.timings.waiting);
  sleep(1);
}
```