A2, headed by managing director Geoff Babidge, has been the top performer on the NZX50 so far this year and its share price has risen by 130 per cent.
Shares in Air New Zealand, the next best performer, are up 61 per cent since January.
JBWere New Zealand equities manager Rickey Ward said A2's result today appeared ahead of market expectations.
"But the expectations were for a pretty damn good result to justify the share price. The share price had rallied almost a dollar from not that long ago.
"It had been strengthening on expectations of a very good result and the company has delivered that," Ward said.
"The cynics will try to point holes or pick holes in it but at the end of the day it's a good result."
Oyvinn Rimer, senior research analyst at Harbour Asset Management, said it was a stellar result from A2's management.
"It clearly illustrates the strong demand particularly for infant formula powder into the Asian market place," Rimer said.
"It showcases that [management] are very competent in navigating what is pretty tough market conditions. There are so many variables at play and seen so many other companies executing into the infant formula space, it is testament to very solid management," he said.
Rimer didn't think A2's shares were overvalued.
"It's really easy to get fixated on a multiple [of share price to earnings per share] for a company like this. But if you look at its earnings, its earnings are growing faster than the share price," Rimer said.
"Technically it's actually cheaper now than it has ever been in terms of future earnings prospects. Earnings from next year are expected to increase significantly again ... the consensus numbers have always been behind the eight-ball on this company," Rimer said.
- Additional reporting: BusinessDesk
