WELLINGTON, Feb. 14 (Xinhua) -- Food prices increased 0.8 percent in the year to January 2018, which was the smallest annual increase in food prices since April 2017, New Zealand's statistics department Stats NZ said on Wednesday.

"Some dairy products and produce items were affected by adverse conditions during winter and spring, which has contributed to higher prices over the past nine months," consumer prices manager Geoffrey Wong said in a statement.

Butter prices increased 43 percent in the year to January 2018, reaching their highest-ever level. Avocado and pumpkin prices more than doubled in the year to January 2018, according to Stats NZ.

"These higher annual prices for avocado and pumpkin were partly offset by lower prices for apples, tomatoes, and carrots," Wong said.

New Zealand food prices rose 1.2 percent in the month to January 2018, with increases in all five subgroups, he said.

Grocery food was the highest upwards contributor, rising 1.4 percent, led by higher prices for bread and chocolate. These rises were influenced by items coming off December last year specials, according to Stats NZ.

Meat, poultry, and fish prices rose 2.4 percent in January, to reach their highest level since January 2016. Beef prices were at their second-highest level since the series began, it said.