Landlords have been buoyed by an influx of quality and international retail outlets – coupled with higher consumer demand – which has meant a shift in vacancy rates from 6 per cent in early 2011 to 2.6 per cent last month, a Savills Australia survey shows.

The survey focused on Melbourne's main retail core bounded by Collins, Swanston, Elizabeth and Lonsdale streets, a geographic rectangle where just 29 shops were empty, down from a post-GFC high of 64 in 2011.

Over the last 12 months, vacancy had reduced from 3.8 per cent to 2.6 per cent, marking the "fifth consecutive year of declining vacancy despite the addition of several new CBD retail centres", Savills researcher Monica Mondkar said.

Australian Retailers Association executive director Russell Zimmerman said Australian Bureau of Statistics retail figures released on Friday showed 4 per cent year-on-year growth, nationally, in January.

The Melbourne CBD "always had a strong retail trade sector", which was being boosted by international retailers coming into Australia, he said.

Retail trade in Victoria grew 5 per cent in the same period and consumer confidence was also up slightly as the city's residential population and workforce continued to expand.

Melbourne's shoppers have been reinvigorated by an influx of international brands, lured by the Emporium and other retail developments, although that may pose a continuing challenge to local retailers, Deloitte Access Economics' latest retail forecast, released on Tuesday, says.

"Many of the major global players are still absent from the Australian market, but more are likely to enter in the coming years which will further intensify competition in Australian retailing," it said.

The "turbulent" global backdrop was likely to have an impact this year, Deloitte said.

"There are concerns about whether the Australian retail sector can continue to stare down the global challenges. They will likely work through to reduce the rate of retail sales growth through the course of 2016."

Savills retail director Michael Di Carlo said while the growth in international fashion brands had attracted shoppers to the city's core, the increasing population was driving the rise in food, beverage and services retailing.

Mr Di Carlo said retailers were shifting their focus to laneway locations.

Local footwear brand Wittner Shoes was expanding into a store in Howey Place and Little Collins Street in a 105-square-metre tenancy leased on a five-year term, with options, at a rental of circa $4000 a square metre per annum net.

Wittner will begin fitting out the store with a view to opening in the next few weeks.

Mr Di Carlo said there had been minimal movement in rents which ranged between $1500 a square metre for CBD shopping centre space and $11,000 a square metre for prime space in Bourke Street Mall.