Nationals foreign buyers tax numbers "not credible": economists

The National Party's tax plan has an enormous hole in it, according to analysis by economists from both sides of the political spectrum. Their concerns centre on the proposed foreign home buyers tax - which National is relying on to raise $740 million a year. But using real estate data from Corelogic, the economists Michael Reddell, Sam Warburton and Nick Goodall, have calculated that revenue will fall short by 60 to 70 percent. Kathryn speaks with Sam Warburton and Corelogic's Nick Goodall.