Using Time Trending for 2015/2016 Property Valuation

How Time Trending Is Used

By law, residential properties must be valued solely by the market approach, using comparable verified sales from the study period July 1, 2012 through June 30, 2014 to determine value for the 2015 reappraisal. If necessary, sales from the prior five years can also be used. These same statutes require the adjustment of sales prices within this study period to the end of the data period, June 30, 2014.

Sales of residential homes which took place during the last assessment date, July 1, 2012–June 30, 2014, were analyzed to establish the residential time trend adjustments.

Since the law requires that sales prices be adjusted to the June 30, 2014 appraisal date, all homes that sold in our study period are valued as sold on June 30, 2014, and the “time adjusted sales prices” reflect market conditions on that date.

Time Trend Adjustments are applied using this process: 1. Look up the Time Trend Adjustment based on the specific Market Area, month and year in which the property sold.
2. Calculate Adjusted Sale Price:
Original Sale Price
x Time Trend Adjustment
= Adjusted Sale Price
Example for home sold in Market Area 101 in January of 2012 for $400,000: The Time Trend Adjustment for properties in Market Area 101, sold in January 2012 is 1.0100:
$400,000 (Original Sale Price)
x 1.0100 (Time Trend Adjustment)
= $404,000 (Adjusted Sale Price)

time trend adjustment example

Residential 5-Year Time Trend Adjustments (July 1, 2009 through June 30, 2014)

Market Area Maps for Single Family Residential Properties

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