How Mass Appraisal Works

Targeting a 91% ratio would leave us vulnerable to the continuing robust real estate market. Like everything else in assessing, the date of reckoning is April 1. The study we conducted for this most recent update took place in April and May and used sales from the twenty-four-month period of April 1, 2023, to March 31, 2025. If we were to establish a ratio of 91% now, there’s no doubt it would be below 91% by April 1, 2026. In order to certify at 100% our ratio needs to be at or above 91% for all qualified sales that took place for the twenty-four-month period that ended on April 1, 2025.

I settled on 96% as the target ratio. This would allow our ratios to erode by a further 5% between April 2025 and April 1, 2026. Everything I read and hear indicates real estate will continue to hold steady in value in 2026 and the recent sales since April have proven that.

We need to bring each grouping up to 96% or so. In the case of single-family dwellings, the aggregate number has to move from 87% to 96%.

We accomplish this by adjusting the square foot value of each single-family dwelling’s building style until the ratio for each type – ranch, cape, colonial, etc. – is as near to 96% as possible. In this way all groupings are individually equalized at or close to 96% and the single-family dwelling grouping averages out to 96%.

We adjust land values in a similar manner, balancing one adjustment against the other to ensure the final outcome is correct so that all ratios having to do with any individual property is as close to the target ratio as is possible.