Nearly one in four offices in the centre of Perth are empty with the office vacancy rate more than double the national average and at its highest level in more than 20 years.

The office market vacancy rate hit 21.8 per cent in the six months to July, up from 19.6 per cent as the economy continues to splutter due to a slowdown in the resources industry. Australia’s national office market vacancy rate fell from 10.5 per cent to 10.4 per cent with…