# RateLine

> A rate with its timestamp. Never one without the other.

Source: https://lopifi.com/components/rate-line
Part of: Lopifi — US GAAP books on autopilot, reviewed by a CPA (https://lopifi.com)

---

- **Family:** Swaps & FX — 
- **Status:** Implemented
- **Spec:** https://lopifi.com/docs/catalog/04-swaps-fx

## Install

```bash
npx shadcn@latest add @lopifi/theme
npx shadcn@latest add @lopifi/rate-line
```

## Specification

```tsx
<RateLine from="USD" to="EUR" rate={0.91842} asOf={t} />
// 1 USD = 0.91842 EUR · 12s ago
```

5 significant figures, `tnum`. **The timestamp is not optional** — the component has no variant without it.

Live variant flashes on update ([value flash](../motion/03-catalog.md#value-flash)), throttled to one flash per 400ms.

## Rules this component obeys

Money is minor units, never floats. `null` is not `0` and neither is redacted. Negatives render in accounting parentheses with the parenthesis column reserved on both sides. Debit and credit are two columns. Per-currency decimal places. Polarity is explicit — up is not always good. Every figure states its period, entity, currency, basis and as-of.