BALLOT for an HDB flat. Get married and move in. Fulfil the minimum occupation period. Sell the flat and upgrade to a condominium. This is the typical real estate journey of many Singaporean couples.

But data suggests the final step is becoming increasingly difficult, with fewer owners of Housing and Development Board flats able to afford an upgrade. The numbers also point to a potential opening for buyers who can wait.

Buyers of new condominiums in the outside central region (OCR) – the suburbs of Singapore, where property is typically more affordable – are no longer mostly HDB dwellers.