Zillow Economics Data

### Context

Zillow's Economic Research Team collects, cleans and publishes housing and economic data from a variety of public and proprietary sources. Public property record data filed with local municipalities -- including deeds, property facts, parcel information and transactional histories -- forms the backbone of our data products, and is fleshed out with proprietary data derived from property listings and user behavior on Zillow.

The large majority of Zillow's aggregated housing market and economic data is made available for free download at zillow.com/data.

### Content

**Variable Availability:**

*Zillow Home Value Index (ZHVI)*: A smoothed seasonally adjusted measure of the median estimated home value across a given region and housing type. A dollar denominated alternative to repeat-sales indices. Find a more detailed methodology here: http://www.zillow.com/research/zhvi-methodology-6032/

*Zillow Rent Index (ZRI)*: A smoothed seasonally adjusted measure of the median estimated market rate rent across a given region and housing type. A dollar denominated alternative to repeat-rent indices. Find a more detailed methodology here: http://www.zillow.com/research/zillow-rent-index-methodology-2393/

*For-Sale Listing/Inventory Metrics*: Zillow provides many variables capturing current and historical for-sale listings availability, generally from 2012 to current. These variables include median list prices and inventory counts, both by various property types. Variables capturing for-sale market competitiveness including share of listings with a price cut, median price cut size, age of inventory, and the days a listing spend on Zillow before the sale is final.

*Home Sales Metrics*: Zillow provides data on sold homes including median sale price by various housing types, sale counts (methodology here: http://www.zillow.com/research/home-sales-methodology-7733/), and a normalized view of sale volume referred to as turnover. The prevalence of foreclosures is also provided as ratio of the housing stock and the share of all sales in which the home was previously foreclosed upon.

*For-Rent Listing Metrics*: Zillow provides median rents prices and median rent price per square foot by property type and bedroom count.

**Housing type definitions:**

*All Homes:* Zillow defines all homes as single-family, condominium and co-operative homes with a county record. Unless specified, all series cover this segment of the housing stock.

*Condo/Co-op:* Condominium and co-operative homes.

*Multifamily 5+ units*: Units in buildings with 5 or more housing units, that are not a condominiums or co-ops.

*Duplex/Triplex*: Housing units in buildings with 2 or 3 housing units.

*Tiers*: By metro, we determine price tier cutoffs that divide the all homes housing stock into thirds using the full distribution of estimated home values. We then estimate real estate metrics within the property sets, Bottom, Middle, and Top, defined by these cutoffs. When reported at the national level, all Bottom Tier homes defined at the metro level are pooled together to form the national bottom tier. The same holds for Middle and Top Tier homes.

**Regional Availability:**

Zillow metrics are reported for common US geographies including Nation, State, Metro (2013 Census Defined CBSAs), County, City, ZIP code, and Neighborhood.

We provide a crosswalk between colloquial Zillow region names and federally defined region names and linking variables such as County FIPS codes and CBSA codes. Cities and Neighborhoods do not match standard jurisdictional boundaries. Zillow city boundaries reflect mailing address conventions and so are often visually similar to collections of ZIP codes. Zillow neighborhood boundaries can be found here.

Suppression Rules: To ensure reliability of reported values the Zillow Economic Research team applies suppression rules triggered by low sample sizes and excessive volatility. These rules are customized to the metric and region type and explain most missingness found in the provided datasets.

**Additional Data Products**

The following data products and more are available for free download exclusively at [Zillow.com/Data][1]:

- Zillow Home Value Forecast
- Zillow Rent Forecast
- Negative Equity (the share of mortgaged properties worth less than
mortgage balance)
- Zillow Home Price Expectations Survey
- Zillow Housing Aspirations Report
- Zillow Rising Sea Levels Research
- Cash Buyers Time Series
- Buy vs. Rent Breakeven Horizon
- Mortgage Affordability, Rental Affordability, Price-to-Income Ratio
- Conventional 30-year Fixed Mortgage Rate, Weekly Time Series
- Jumbo 30-year Fixed Mortgage Rates, Weekly Time Series

### Acknowledgements

The mission of the Zillow Economic Research Team is to be the most open, authoritative source for timely and accurate housing data and unbiased insight. We aim to empower consumers, industry professionals, policy makers and researchers looking to better understand the housing market.

To see more of our mission in action, we invite you to learn more about us and to check out our collection of research briefs, stories, data tools and past presentations at https://www.zillow.com/research/

### Inspiration

Zillow, and the Zillow Economic Research Team, firmly believe that not only do data *want* to be free, data are *going* to be free. Instead of simply publishing raw data, we believe in the power of pushing data up the ladder from raw data bits, to actionable information and finally to unique insight. We aim to answer questions of all kinds, even questions our users may not have known they had before coming to us. When done right, we firmly believe this process of turning data into insight can be transformational in people's lives.

Please join us on this journey, and we're excited to see what insights you can discover hidden amongst our data!

[1]: https://www.zillow.com/research/data/

### 背景信息
Zillow 经济研究团队从各种公共和专有来源收集、清洗并发布住房和经济数据。公共产权记录数据，包括地契、物业事实、地块信息和交易历史，构成了我们数据产品的基础，并辅以从房产列表和 Zillow 上的用户行为中获取的专有数据进行完善。

在 zillow.com/data 网站上，Zillow 的绝大多数汇总住房和经济数据均可免费下载。

### 数据内容
**变量可用性：**
*Zillow 房屋价值指数 (ZHVI)*：针对特定区域和住房类型的平均估计房屋价值的平滑季节性调整指标。一种以美元计价的重复销售指数的替代方案。更详细的方法论请参阅：http://www.zillow.com/research/zhvi-methodology-6032/

*Zillow 租金指数 (ZRI)*：针对特定区域和住房类型的平均估计市场租金的平滑季节性调整指标。一种以美元计价的重复租金指数的替代方案。更详细的方法论请参阅：http://www.zillow.com/research/zillow-rent-index-methodology-2393/

*待售列表/库存指标*：Zillow 提供了许多变量，用于捕捉当前和历史上的待售列表可用性，通常从 2012 年至当前。这些变量包括中位价列表价格和库存计数，按各种物业类型划分。捕捉待售市场竞争力的变量包括降价列表的份额、中位价降价幅度、库存的年龄以及列表在 Zillow 上待售直到交易最终完成之前所花费的天数。

*房屋销售指标*：Zillow 提供了已售房屋的数据，包括按住房类型划分的中位销售价格、销售数量（方法请参阅：http://www.zillow.com/research/home-sales-methodology-7733/）以及称为周转率的标准化销售量视图。还包括房屋所有权丧失的普遍性，作为住房存量的比率以及所有销售中房屋之前已被丧失所有权的份额。

*待租列表指标*：Zillow 提供了按物业类型和卧室数量划分的中位租金价格和中位每平方英尺租金价格。

**住房类型定义：**
*所有住宅*：Zillow 将所有住宅定义为有县记录的单户住宅、公寓和合作社住宅。除非另有说明，所有系列均涵盖这一住房存量部分。

*公寓/合作社*：公寓和合作社住宅。

*多户住宅（5个或更多单位）*：非公寓或合作社的5个或更多住宅单位的单元。

*复式/三式住宅*：有2个或3个住宅单位的住宅单元。

*层级*：按大都市区，我们确定价格层级截止点，将所有住宅住房存量分为三等份，使用估计房屋价值的完整分布。然后在这些属性集合内估算房地产指标，分别为底部、中部和顶部层级，由这些截止点定义。在国家层面报告时，所有在大都市区定义的底部层级住宅汇集在一起形成国家底部层级。中部和顶部层级住宅也是如此。

**区域可用性：**
Zillow 指标适用于常见的美国地理区域，包括国家、州、大都市（2013 年人口普查定义的 CBSA）、县、市、ZIP 码和社区。我们提供了一种从口语化的 Zillow 区域名称到联邦定义的区域名称以及链接变量（如县 FIPS 码和 CBSA 码）之间的交叉对照表。城市和社区不匹配标准司法管辖权边界。Zillow 城市边界反映了邮寄地址惯例，因此通常与 ZIP 码集合的外观相似。Zillow 社区边界可在以下位置找到。

**抑制规则**：为了确保报告值的可靠性，Zillow 经济研究团队应用了由低样本量和过度波动触发的抑制规则。这些规则针对指标和区域类型定制，并解释了在提供的数据库中发现的绝大多数缺失值。

**附加数据产品**
以下数据产品以及更多产品可免费下载，专用于 [Zillow.com/Data][1]：
- Zillow 房屋价值预测
- Zillow 租金预测
- 负资产（抵押财产价值低于抵押余额的份额）
- Zillow 房价预期调查
- Zillow 住房愿望报告
- Zillow 海平面上升研究
- 现金买家时间序列
- 买卖盈亏平衡时间点
- 贷款可负担性、租金可负担性、房价收入比
- 传统30年固定利率抵押贷款利率，周时间序列
- 大额30年固定利率抵押贷款利率，周时间序列

### 致谢
Zillow 经济研究团队的使命是成为最开放、最具权威性的及时准确住房数据和客观见解的来源。我们旨在赋权消费者、行业专业人士、政策制定者和研究人员，以更好地了解住房市场。

要了解更多关于我们的使命，请访问我们的网站并查看我们的研究简报、故事、数据工具和往昔演示文稿：https://www.zillow.com/research/

### 启示
Zillow 和 Zillow 经济研究团队坚信，数据不仅渴望自由，而且必将走向自由。我们不仅相信发布原始数据的力量，更相信将数据从原始数据比特推向可行动信息，最终到独特见解的阶梯式提升的力量。我们旨在回答各种问题，甚至包括用户在我们到来之前可能未曾意识到的问题。当正确执行时，我们坚信将数据转化为见解的过程可以改变人们的生活。

请加入我们的旅程，我们期待看到您在我们数据中发现的见解。

[1]: https://www.zillow.com/research/data/