As a follow on from my last comment, the prices of homes have nothing to do with the tax rate. The concept of ratable value is different from valuing homes through conventional real-estate valuation principles.

The only factors would be (a) land area, (b) land use permissions and (c) land placement (one can imagine high value districts and low value districts and can easily define categories of placement e.g. Ultra-high, high, average, low, ultra-low) for each class of permitted use. This would set the rate on a very algorithmic basis having nothing to do with the ebb and flow of house prices, since we’re not talking about transacting home title transfers.