Why is the tax amount increasing even though the appraisal value of the land is decreasing due to the decrease in land prices?

Prior to fiscal 1994, land valuation levels for fixed asset taxes varied by municipality, and were assessed at levels significantly lower than the published land prices. In order to correct this, the system was revised in 1994, and the appraisal value was unified nationwide so that it was about 70% of the published land price.
However, if we combine this revised "assessment value" (= the number that is the basis for calculating the original tax burden) with the "tax base amount" that is the basis for calculating the actual tax burden, the tax burden on taxpayers will increase rapidly. Therefore, the “burden adjustment measures”, which are a mechanism to gradually raise the tax base amount and gradually bring the assessed value closer to each other, were established and are still being implemented.
Therefore, the tax amount for all land does not increase regardless of land price trends, but only for land where there is a difference between the assessed value and the standard taxable amount.