docs/guides/source_data.md

# Japan Data Sources

## Primary Source: e-Stat
The **[e-Stat Portal Site of Official Statistics of Japan](https://www.e-stat.go.jp/en)** is the centralized portal for Japanese government statistics.

## Key Datasets

### 1. Population & Demographics
*   **Dataset Name:** Population Census
*   **Description:** The most comprehensive survey conducted every 5 years. Covers population, age, sex, marital status, household structure, etc.
*   **Navigation:** `Statistics > Population and Households > Population Census`
*   **Link:** [2020 Population Census Database](https://www.e-stat.go.jp/en/stat-search/database?page=1&toukei=00200521&tstat=000001136464)

### 2. Income & Economy
*   **Dataset Name:** National Survey of Family Income, Consumption and Wealth
*   **Description:** Detailed data on household income, savings, liabilities, and consumption patterns.
*   **Navigation:** `Statistics > Business, Household, Economy > National Survey of Family Income, Consumption and Wealth`
*   **Link:** [Family Income Survey Data](https://www.e-stat.go.jp/en/stat-search/files?page=1&toukei=00200564)

### 3. Labor & Wages
*   **Dataset Name:** Wage Structure Basic Statistical Survey
*   **Description:** Information on wages, working hours, and employment details.
*   **Navigation:** `Statistics > Labor and Wages > Wage Structure Basic Statistical Survey`
*   **Link:** [Wage Structure Data](https://www.e-stat.go.jp/en/stat-search/files?page=1&toukei=00450091)

## How to Download
1.  Navigate to the specific dataset using the links above or the search bar on e-Stat.
2.  Select the "File" or "Database" tab.
3.  Look for the **Download** icon (usually CSV or Excel format).