Melbourne’s CBD vacancy rate has hit 19.6 per cent, the highest since 1995, as a thinning pool of tenants switch into in efficient new towers on reduced footprints, leaving behind a generation of old, unloved and rapidly emptying hulks.

Sydney’s vacancy rate is also rising steadily, up more than a percentage point, quarter-on-quarter, to 15.6 per cent in the June quarter. A year ago, Melbourne’s vacancy rate was 16.2 per cent, according to JLL.