Melbourne has been crowned the world's most liveable city for an historic sixth year running by the Economist Intelligence Unit (EIU).  It combines this title with being Australia's fastest growing city, with the population increasing by around 100,000 people a year.

Recent ABS data shows Melbourne grew by 91,600 between 2014 and 2015—an average of 1,760 people per week. At this rate, Melbourne is tipped to overtake Sydney as Australia's largest city by 2056.

But what is driving the growth?

A closer look at ABS figures and deeper latest government job statistics reveals a nuanced web of driving forces—from job security to growing regional migration.

More Australians want to call Melbourne home

An increasing number of Australians are choosing to move to Melbourne. The latest census shows that Victoria gained 73,500 internal migrants, helping to make it the fastest-growing state in Australia.

Sydney-siders in particular are deciding to move south. Between 2013 and 2014, around 11,200 resident Australians moved from Sydney to Melbourne.

Demographic experts attribute this to Sydney's rising property prices. Frustrated by unaffordable housing, they argue, many Sydney residents are looking to Melbourne as an alternate home.  

Indeed, since the 2001 census, Melbourne's population has grown by one million people. Sydney in contrast, has grown by 750,000 people—a difference of 250,000.

Business is booming

Melbourne's strong economic performance is another factor behind the population boom.  According to SGS Economics and Planning, the Victorian capital is one of the country's leading economies, outperforming Sydney and Perth with an annual growth rate of 3.1 per cent.

The city contributes 6 percent of Australia's Gross Domestic Product and is home to six of the top 10, and 29 of the top 100 Australian companies. More top companies have headquarters in Melbourne than in Sydney, making it an attractive destination for both domestic and international migrants.

The development of residential and professional office towers along the city's Southbank and Docklands has helped cater to the growth in the professional services sector, while also contributing to a boom in the construction industry.

Still Australia's most liveable city

Melbourne has been ranked the world's most liveable city six years in a row. In 2016, the EIU's Global Liveability Index gave Melbourne a score of 97.5 out of 100 based on its "relative comfort" in healthcare; culture and environment; education; and infrastructure—for which it scored full marks.

Affordable housing, ample green spaces and reliable public transport also contribute to the city's strong appeal. The city's rich cultural diversity is another factor. A recent study by the City of Melbourne found that almost half of all residents were born overseas, and it still hosts the largest Greek population outside of Athens.This mix of cultural diversity, natural beauty and dependable public services has made the city especially attractive to international migrants.

Between 2013 and 2014, Victoria received over 54,000 international migrants, the majority of whom settled in Melbourne.