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Maricopa County goes live with Assessment Analyst® GAMA

Cloud-based geographic-assisted mass appraisal system enables quicker, equitable and defensible property valuations

SALT LAKE CITY, Utah—2023 IAAO Annual Conference—August 29, 2023—Esri Canada today announced that Maricopa County in Phoenix, Arizona has gone live with Assessment Analyst® GAMA, a cloud-based geographic-assisted mass appraisal system that enables assessors to deliver more accurate, equitable and defensible property assessments faster.

Assessment Analyst GAMA aligns with the Maricopa County Assessor’s Office Strategic Plan and supports its goal of delivering data-driven assessments for the 1.8 million real estate properties within its jurisdiction. Assessors can now easily combine data from the County’s computer-assisted mass appraisal (CAMA) system with spatial data from their geographic information system (GIS) to get a more accurate picture of property characteristics. 

“We are pleased to introduce this important new system to improve service to Maricopa County residents and property owners,” said Maricopa County Assessor Eddie Cook. “Our focus at the Maricopa County Assessor’s Office is to operate one of the most efficient and effective offices in the country, and this is a key step forward in that direction.”

The new system increases efficiency by enabling assessors to unify their data management workflows. They can now enter, track and manage all their data in the County’s GIS and CAMA systems from a single screen. They have also gained the ability to load sales and income regression models directly into Assessment Analyst GAMA, allowing for on-demand valuations of all parcel classes. This process previously required the transfer of data between multiple systems.

Assessment Analyst GAMA improves the accuracy of property assessments by allowing assessors to enter business rules that integrate numerous data checks into the parcel and account validation and valuation processes. This enables them to identify and correct any erroneous or missing data throughout the year.

The system’s advanced search capability provides assessors with convenient self-serve access to critical data, without the need to submit report requests to the County’s IT department. Being able to visualize and access various data layers on a map has also been a huge improvement from their legacy system.

“Location is integral to property assessments,” said Michael Lomax, managing director of Assessment at Esri Canada. “Moving to a geographic-assisted mass appraisal system gives Maricopa County the advantage of leveraging location to connect various data for a better understanding of properties and ultimately more precise valuations.”

To see Assessment Analyst GAMA in action, visit booth 121 at the 2023 IAAO Annual Conference (August 27-30 in Salt Lake City, Utah) or at

About the Maricopa County Assessor’s Office
Each year, the Maricopa County Assessor’s Office values over 1.8 million real and personal property parcels and accounts with a full cash value of over $1 trillion. The Assessor’s Office ensures that fairness, equity and respect is present in every aspect of its operations to secure quality services for residents’ property. To achieve this, the Assessor’s Office continues to innovate and anticipate the changing needs of the community and embrace the latest technology. More information can be found at:

About Esri Canada 
Founded in 1984, Esri Canada provides geographic information system (GIS) solutions that empower people in business, government and education to make informed and timely decisions by leveraging the power of mapping and spatial analytics. In 2012, Esri Canada established a property assessment practice focused on enabling fair and equitable mass appraisals, valuations and property assessments using GIS-centric solutions. Assessment organizations turn to Esri Canada’s Assessment team for their unparalleled knowledge and international experience in the application of GIS to solve assessment management business needs. Our team of GIS experts and domain specialists has also developed specific tools and methods to effectively deliver all assessment management protocols compliant with IAAO standards. More information can be found at Follow Esri Canada Assessment Analyst on LinkedIn

For media inquiries, please contact:

Maricopa County Assessor’s Office

Esri Canada