For the first 10 years of consolidation, the citywide tax rate for general government was rolled back each year as the merger of city and county governments led to savings and efficiencies. That hasn't always been the case since then, but in the past 10 years, at least, tax rate reductions have occurred each year. This was partly the result of productivity gains. But growth in the tax roll also played a major part.
Growth comes from new construction and from the rising value of existing property.
Every year there is a calculation made to determine what tax rate would produce the same amount of revenue as the previous year. This calculation excludes new construction, so even at the rollback rate the city gains revenue. Each of the past 10 years, the City Council has set the tax rate above the rollback rate. The effect is relatively small on the average home. In some years the difference between the actual rate and the rollback rate has been small, as in 1991 during an economic slowdown.