Annual assessments reflect any changes in property value for that year.  Adding or removing improvements may increase or decrease a property’s value, and the annual assessment reflects this.

A general assessment looks at more than improvements to properties, and must happen within 10 years of the previous general assessment.  A general assessment takes into account factors like inflation, deflation, and other factors that can change the value of a property over time that are not necessarily related to the land or improvements (like a change of zoning etc.). Once a general assessment is complete, new assessed values for all property using that common base year is created, and is the basis on which annual assessments are done.