# Zona real estate indexes

## 1. Zona real estate index

Zona real estate indexes are proprietary price indexes that track the median price per square foot / meter of all second-hand residential real estate in a city. Indexes are compiled from realized real estate transactions across a city and are updated onchain on an hourly basis.&#x20;

Zona indexes represent a massive improvement upon existing real estate indexes, due to:

1. **Higher update frequency:** Zona indexes are updated once an hour, as opposed to weekly or even quarterly for traditional indexes.
2. **Higher data completeness:** Zona indexes source data from all second-hand real estate transactions in a given city, whereas some traditional indexes may only include data from certain brokers.&#x20;

Indexes are typically at a city-level granularity, although they can extended to a district-level or country-level index based on user demand.



## 2. Data Pipeline

1. **Collect:** Zona collects data on all realized real estate transactions for a city. The data is taken from multiple trustworthy local sources (such as real estate data service providers or agencies) to ensure reliability and redundancy.&#x20;
2. **Cleanse:** The data is then cleansed for errors (e.g. duplicates or extreme outliers). A moving average is then applied to the index, which reduces price spikes induced by outliers and allows for a smooth trading experience.
3. **Verify:** The index is backtested against existing industry-leading indexes, ensuring that the price is correct.
4. **Push:** The index is bridged onchain via an oracle service.
5. **Use:** Zona users trade against this price index via the Zona exchange.

<figure><img src="https://1459145712-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F7ahBG74qgSNVUFLp9ZYl%2Fuploads%2FuXRu104eMAAwU3stM4uv%2F2_data_pipeline.png?alt=media&#x26;token=a011b2d2-4bf4-49d0-88ee-e5dea7346e43" alt=""><figcaption><p>Zona's data pipeline</p></figcaption></figure>



## 3. What indexes will Zona support?

During our initial developmental stage, Zona plans to support major crypto cities first, such as Singapore, Dubai, Hong Kong, London, and more. We ultimately aim to support as many real estate markets around the globe as we can and welcome your feedback as to which cities we should integrate next.&#x20;
