Residential properties, by law, must be valued solely by the market approach, using comparable verified sales from the study period ending June 30 prior to January of the reappraisal year. These statutes require the adjustment of sale prices to reflect changing market conditions. This is known as time trending. Sales of residential property that took place during the study period are analyzed to establish necessary time adjustments. Since the law requires that sale prices be adjusted to account for appreciation or decline in the market up to the June 30 appraisal date, it’s as if all homes that sold during the study period were sold on the June 30 appraisal date.