The Rolex Rankings were released overnight (tues) and the teenager finished the LPGA Tour season in third on 10.13 average points behind Stacy Lewis (10.45) and Korea's Inbee Park (11.44) who has held the top spot for six weeks.
Ko, who has previously been ranked as high as second, ended the LPGA season in style last week as she won the Tour Championship event in Florida, which propelled her to the top of the order of merit as she banked a record $1.9 million payday.
The women's golf rankings are worked out on the number of points won divided by the number of tournaments played in the past two years with extra weight given to the current year's events.
As for the Kiwi men, Ryan Fox was the big mover after he finished in a share of seventh at the Australian Open during the weekend as he climbed to 291st from 353rd in the world.
Danny Lee remains New Zealand's highest-ranked player at 217, although Fox's rise took him ahead of PGA Tour players Steven Alker (297) and Tim Wilkinson (330).
Meanwhile, Reuters has reported that Ko will study psychology through Seoul's Korea University next year, while balancing the demands of her playing schedule.
"I'll have to listen to what the university says to decide how I will do my studies," she told Yonhap news agency in an interview on Sunday.
"I'll have to make sure I submit the required papers and projects as the majority of my classes will be done online."
Ko, who completed her high school education at Pinehurst School on the North Shore, has long spoken of pursuing a university degree.
- By Patrick McKendry of NZME
