Roughly 50% of the Hong Kong population live in public rental flats or subsidized housing. Hence, the remaining 50% are potential buyers of private residential property for personal use. Public and subsidized housing are intended for lower income people. Accordingly, it is reasonable to assume that the potential buyers of private housing are the top half of the population in terms of income. Therefore, as the representative household income, I use the income of the 75th percentile of households by income. One-quarter of all households would have higher income, while three-quarters would have  lower income.