> ## Documentation Index
> Fetch the complete documentation index at: https://docs.activeviam.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Curve

The **Curve** (Underlying) refers to the relevant credit issuer spread curves (bond and CDS) [MAR21.9](https://www.bis.org/basel_framework/chapter/MAR/21.htm?inforce=20230101\&published=20200327#paragraph_MAR_21_20230101_21_9)(1).

| Field                   | Key | Description                                         |
| ----------------------- | --- | --------------------------------------------------- |
| As-of Date              | Y   | Timestamp (at close of business) for the data (T-1) |
| Curve Name (Underlying) | Y   | Name of the issuer credit spread curve              |
| Risk Class              | Y   | “CSR non-Sec”                                       |
| Bucket                  |     | 1-18                                                |
| Credit Quality          |     | “IG”, “HY”, or “NR”                                 |
| Sector                  |     | The relevant sector of the curve                    |
| Covered Bond Rating     |     | “high” for AA- and above covered bonds.             |