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King County Department of Assessments

Fair, Equitable, and Understandable Property Valuations

Department of Assessments

500 Fourth Avenue,
Suite ADM-AS-0708,
Seattle, WA 98104

Office Hours:
Mon - Fri
8:30 a.m. to 4:30 p.m.

TEL: 206-296-7300
FAX: 206-296-5107
TTY: 206-296-7888

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Glossary of terms for commercial parcels

IMPROVEMENT
Anything done to raw land with the intention of increasing its value.  A structure erected on the property constitutes one very common type of improvement, although other actions, such as those taken to improve drainage, are also improvements.

IMPROVEMENTS
Buildings, other structures, and attachments or annexations to land that are intended to remain so attached or annexed, such as sidewalks, trees, drives, tunnels, drains and sewers.

INCOME APPROACH
The income approach defines value as the present worth of future benefits arising from the ownership of a property. This definition reflects the principle of anticipation.  Income-producing property typically is purchased for the right to receive the future income stream of the property.  The assessor analyzes this income stream in terms of quantity, quality, and duration and then converts it by means of an appropriate capitalization rate into an indication of market value. The basic formula is:  Value equals income divided by rate.