WELLINGTON — Record global butter prices and higher sales of milk and cream to China, boosted New Zealand's total exports in September, the country's statistics department Stats NZ said on Thursday.

Exports of food preparations, including infant formula, were up by NZ$58 million ($40 million), or 104 percent, in September, and over half of this commodity was exported to China, Stats NZ said.

"The increases in both butter and milk powder were price-driven," international statistics manager Tehseen Islam said in a statement.

Almost 80 percent of milk and cream exported to China. The manager said that milk and cream were mainly volume-driven, especially to China, "though prices were up, too."

Milk powder, butter, and cheese exports reached NZ$791 million in September, up 28 percent on the same month last year, Stats NZ said, adding that the overall goods exports rose 9 percent to NZ$3.8 billion, mainly driven by milk powder, butter and cheese.

Milk fats including butter led the rise in dairy-related sales, up 43 percent to NZ$207 million, even though volumes fell, the department said, adding that milk powder and milk and cream also contributed to the rise.

The average unit price of butter was NZ$8,280 a ton in September, compared with less than NZ$5,000 a ton in the same month last year, it said.

Compared with September 2016, imports rose 1.4 percent to reach NZ$4.9 billion, the second highest imports value on record, Stats NZ said, adding that the monthly trade deficit was NZ$1.1 billion, or 30 percent of exports, NZ$245 million lower than the deficit in September 2016.