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2025/2026 Time Trending

Using Time Trending for 2025/2026 Property Valuation

What Is Time Trending and How Is It Used?

2025/2025 Comparable Sales

Time Trend Adjustments

By Colorado law, residential properties must be valued solely by the market approach using verified sales of similar homes. The study period of July 1, 2022 to June 30, 2024 was used to determine values for the 2025 reappraisal. The law also requires that all sales prices within the study period are time adjusted to reflect the actual market conditions on the June 30, 2024 appraisal date.

Calculating the Time Trend Adjusted Sales Price

Look up the Time Trend Adjustment for the specific Market Area and property type, month and year in which the property was sold using the 2025 Residential Time Trend information. Use this formula to calculate the adjusted price: original sales price X time trend adjustment = adjusted sales price.

Original
Sales
Price
X Time
Trend
Adjustment
= Adjusted
Sales
Price

Example
Take a home sold in Market Area 102 in February of 2021 for $600,000. The time trend list shows the Time Trend Adjustment factor is 1.2794.

time trend adjustment table 2023

Using the formula above:

$600,000 X 1.2794 = $767,640

The adjusted sales price is $767,640.

Contact Us

Assessor

Phone: 303-441-3530
Fax: 303-441-4996

Email

Mailing Address

PO Box 471
Boulder, CO 80306-0471

Hours: 7:30 a.m. to 5 p.m.
Monday-Thursday
Closed Friday

Locations

Assessor Boulder and Longmont Drop Boxes

Boulder

1325 Pearl St., 2nd floor
Boulder, CO 80302
Hours: 7:30 a.m. to 5 p.m.
Monday-Thursday
Map and Directions Boulder Location

Longmont

515 Coffman St., Suite 114
Hours: 7:30 a.m. to 5 p.m.
Monday only
Map and Directions Longmont Location

Lafayette

1755 S Public Road
Hours: 7:30 a.m. to 5 p.m.
Tuesday only
Map and Directions Lafayette Location