** Shares of New Zealand's a2 Milk ATM.NZ slip as much as 13.9% to NZ$9.50, their lowest level since September 26, 2025
** Auckland-headquartered dairy firm set for weakest trading session since August 19, 2024, if current losses hold
** Trading halted in co's shares on ASX
** Total number of births in co's key market, China, falls to its lowest level in decades
** "Multiples are too high with China's birth rate weakening," says Mathan Somasundaram, CEO at Deep Data Analytics, adding that ATM offers Chinese retail exposure
** Stock down 9.6% in January so far
(Reporting by Shivangi Lahiri in Bengaluru)
((shivangi.lahiri@thomsonreuters.com))