“Investors are just as likely to buy new as they are to buy old,” Mr Mortlock says. “You can get just as much depreciation on an existing property as you do on a new one.”

Investors like new and existing

His data of 4001 investors shows 25.12 per cent of investors buy brand new buildings that haven't been lived in and another 17.67 per cent buy homes that have been built brand new for them – leaving roughly 57 per cent for existing housing.

Mr Mortlock is not overly critical of Labor's negative gearing policy and said if they really have to change he would rather see a cap on the number of homes rather than a restriction on the types of housing. Older homes can require a lot of work to keep in the rental supply pool.

“Investors who have one negatively geared property need that tax benefit more than the people with multiple homes,” Mr Mortlock said.

His figures are in line with those produced by mortgage broker AFG – showing 43 per cent goes to new housing.

One of the largest listed home developers Mirvac reported in February to the Australian Securities Exchange that 33 per cent of its new properties went to investors.

Data from the Australian Bureau of Statistics does not provide a split between investment lending for new housing and investment lending for existing.

The Grattan Institute's Danielle Wood says even assuming that investors buy new and existing property in the same ratio as owner occupiers (for which there is data) the level of investors in new stock would be about 14 per cent.