General Property Tax Act [MCL211.1] (pdf)
SEV represents 50% of the "True Cash Value" of a property in the State of Michigan. It is called an equalized value because the assessor has prepared the value based on sales within the city, the county equalization board has made certain that each city and township have assessed the properties at an equal level, and Michigan State Tax Commission has studied and equalized all the counties within the state to ensure equity between them. The end result each year is that all properties across the state have the same level of assessment regardless of location. This does not mean that all carry the same SEV, only that the SEV of each property is to be at fifty percent of what the usual selling price is expected to be. Until the 1994 passage of the property tax reform ballot proposal, the SEV was the basis of tax bills. Proposal A of 1994 created a new value called the "Taxable Value" for each property. This value reflects the annual "cap" on assessment increases to five percent or the consumer price index-whichever is lower. While the SEV must continue to reflect the actual market, the TV is mathematically determined by the capped value, less the taxable value of any demolition, plus the true cash value of any construction, omitted property, contamination remediation, or any of the other changes as defined in current state laws.
State Tax Commission Guide to Basic Assessing
State Tax Commission Recommended Classification Codes