Government bond yields, daily (TickerLayer)

**For the latest observation, use TickerLayer's API directly:** REST, WebSocket and x402 pay-per-call, documented at https://tickerlayer.com/docs/products/bonds. This dataset is the citable history: every update is a signed, fixed version, so an analysis can name the exact version it used.

## How it is collected

WITAN reads TickerLayer's REST API (`GET /bond/last/{COUNTRY:TENOR}`) twice a day and publishes new observations as the next version. Values are reproduced as TickerLayer reports them; nothing is interpolated or filled in. An unchanged observation is not added twice.

## Fields

| Field | Type | Meaning |
|---|---|---|
| `date` | string | Observation date, `YYYY-MM-DD` |
| `symbol` | string | TickerLayer symbol, `COUNTRY:TENOR` (e.g. `US:10Y`) |
| `country` | string | `US`, `DE`, `FR`, `IT`, `ES`, `UK` |
| `tenor` | string | `1M` … `30Y` |
| `tenor_months` | integer | Tenor in months, for sorting a curve |
| `yield_pct` | number | Yield in percent (`4.54` = 4.54%) |
| `collected_at` | string | When WITAN first read this value from TickerLayer, ISO 8601 UTC |

## Notes

- History starts on the date of the first version, when collection began.
- If TickerLayer revises a value for a date already published, the revised value is added as a new row; for each `(symbol, date)` use the row with the latest `collected_at`.
- Days without a new observation (weekends, market holidays) have no rows.

Example, the US curve on the latest date:

```sql
SELECT tenor, yield_pct FROM records
WHERE country = 'US' AND date = (SELECT max(date) FROM records WHERE country = 'US')
ORDER BY tenor_months;
```

## Source and license

Data from TickerLayer, published on WITAN with TickerLayer's permission. TickerLayer's terms and data licence: https://tickerlayer.com/terms-of-use#data-licence. Readers get it under the WITAN Standard License: use and keep, no resale or republication. Market data is provided as is and is not investment advice (https://tickerlayer.com/market-data-disclaimer).