---
title: "Year Pillars × 10"
method: POST
path: "/bazi/year-pillar-decade"
tags: ["BaZi (Four Pillars)"]
---

# Year Pillars × 10

`POST /bazi/year-pillar-decade`

10 consecutive year pillars from a given starting year.

## Request body

- BaziDecade
  - `startYear` integer, required

## Response `200`

Successful calculation

- object
  - `ok` boolean
  - `data` object
    - `startYear` number, nullable
    - `decade` object[], nullable
      - `solarYear` number, nullable
      - `pillar` string, nullable
      - `animal` string, nullable
      - `element` object, nullable
        - `fixed` string, nullable
        - `cycling` string, nullable
        - `yin` boolean, nullable
    - `disclaimer` string, nullable

## Other responses

- `400` — Validation error
- `401` — Missing or invalid API key

## Changes

- **2026-08-24** `8ab5a768b521` — 5 info
  - added the optional property `data/decade/items/element/cycling` to the response with the `200` status
  - added the optional property `data/decade/items/element/fixed` to the response with the `200` status
  - added the optional property `data/decade/items/element/yin` to the response with the `200` status
  - added the optional property `data/disclaimer` to the response with the `200` status
  - …1 more
- **2026-08-22** `5a17388652f3` — 1 breaking
  - added the new required request property `startYear`

[Change history](https://skmtc.dev/astroway/apis/astroway-calculation-api/changes/bazi/year-pillar-decade/post.md)

---

[API](https://skmtc.dev/astroway/apis/astroway-calculation-api.md) · [All operations](https://skmtc.dev/astroway/apis/astroway-calculation-api/llms.txt) · [OpenAPI document](https://skmtc-service-production.skmtc.workers.dev/v1/apis/astroway/astroway-calculation-api/revisions/4ed0fa90d9dc/schema)