Investors sliced more than $630 million off the value of The a2 Milk Company after chief executive David Bortolussi outlined a plan to sacrifice margins for revenue growth as he adjusts the infant formula company’s approach to the troublesome China market.

Mr Bortolussi wants a2 Milk to achieve $NZ2 billion ($1.9 billion) in annual sales over the medium term but will sacrifice profit margins to get there under his revised growth strategy. This will probably cut the key measure of profitability to the “teens”.