The number of locally held shares in Australian companies that have switched their primary listing to an overseas exchange has more than halved within years and is still falling, raising concerns from investors that an increase in dual listings is driving a wider drain from the ASX.

Figures compiled by the sharemarket operator show the number of local shares in Newmont, which merged with Australia’s largest gold producer, Newcrest Mining, in November 2023, now make up just 11.7 per cent of the register. Shares in Australia had accounted for 31 per cent of the merged company, which has a primary listing in New York.