---
title: prom
description: 'This page provides a detailed explanation of two important functions
  in FINRA ATS data analysis offered by our tool: ''prom'' and ''Chart''. ''prom''
  fetches and processes the most promising stocks based on linear regression while
  ''Chart'' aids in visualizing the dark pool data for improving trading decisions.'
keywords:
- FINRA ATS data
- Trading tool
- Linear regression
- Dark pool data
- Dark pool trades activity
- Stocks analysis
- Data visualization
- Promising stocks
---

import HeadTitle from '@site/src/components/General/HeadTitle.tsx';

<HeadTitle title="stocks.dps.prom - Reference | OpenBB SDK Docs" />

import Tabs from '@theme/Tabs';
import TabItem from '@theme/TabItem';

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<TabItem value="model" label="Model" default>

Get all FINRA ATS data, and parse most promising tickers based on linear regression

Source Code: [[link](https://github.com/OpenBB-finance/OpenBBTerminal/tree/main/openbb_terminal/stocks/dark_pool_shorts/finra_model.py#L214)]

```python
openbb.stocks.dps.prom(limit: int = 1000, tier_ats: str = "T1")
```

---

## Parameters

| Name | Type | Description | Default | Optional |
| ---- | ---- | ----------- | ------- | -------- |
| limit | int | Number of tickers to filter from entire ATS data based on the sum of the total weekly shares quantity | 1000 | True |
| tier_ats | int | Tier to process data from: T1, T2 or OTCE | T1 | True |


---

## Returns

| Type | Description |
| ---- | ----------- |
| Tuple[pd.DataFrame, Dict] | Dark Pools (ATS) Data, Tickers from Dark Pools with better regression slope |
---

</TabItem>
<TabItem value="view" label="Chart">

Display dark pool (ATS) data of tickers with growing trades activity. [Source: FINRA]

Source Code: [[link](https://github.com/OpenBB-finance/OpenBBTerminal/tree/main/openbb_terminal/stocks/dark_pool_shorts/finra_view.py#L188)]

```python
openbb.stocks.dps.prom_chart(input_limit: int = 1000, limit: int = 10, tier: str = "T1", export: str = "", external_axes: Optional[List[matplotlib.axes._axes.Axes]] = None)
```

---

## Parameters

| Name | Type | Description | Default | Optional |
| ---- | ---- | ----------- | ------- | -------- |
| input_limit | int | Number of tickers to filter from entire ATS data based on<br/>the sum of the total weekly shares quantity | 1000 | True |
| limit | int | Number of tickers to display from most promising with<br/>better linear regression slope | 10 | True |
| tier | str | Tier to process data from: T1, T2 or OTCE | T1 | True |
| export | str | Export dataframe data to csv,json,xlsx file |  | True |
| external_axes | Optional[List[plt.Axes]] | External axes (1 axis is expected in the list), by default None | None | True |


---

## Returns

This function does not return anything

---

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