<!-- Public documentation export; not library implementation source. -->
# PeriodParams

[Integration guide](https://docs.lumencharts.com/charting-library/datafeed/history) · [Reference index](https://docs.lumencharts.com/charting-library/api/)

Public contract reference. This declaration describes types and callback shapes; availability is constrained by the linked integration guide and the runtime capability. Legacy product-specific fields are not a promise of implementation.

## from {#from}

```ts
from: number;
```

Use the type signature above and the integration guide for the owning capability.

## to {#to}

```ts
to: number;
```

Use the type signature above and the integration guide for the owning capability.

## countBack {#countback}

```ts
countBack: number;
```

Use the type signature above and the integration guide for the owning capability.

## firstDataRequest {#firstdatarequest}

```ts
firstDataRequest: boolean;
```

Use the type signature above and the integration guide for the owning capability.

---
Documentation page: https://docs.lumencharts.com/charting-library/api/PeriodParams