BEIJING - China's consumer price index (CPI), a main gauge of inflation, grew 2 percent year on year in May, official data showed on Thursday.

The May data narrowed from the 2.3-percent growth rate registered in the previous three consecutive months, when the CPI remained at its highest level since July 2014, data from the National Bureau of Statistics (NBS) showed.

NBS statistician Yu Qiumei attributed the inflation growth mostly to high food, cigarette and wine prices.

Pork prices skyrocketed in May by 33.6 percent year on year, contributing 0.77 percentage points of CPI growth, while vegetable prices jumped by 6.4 percent, accounting for 0.14 percentage points of CPI growth.

Food prices soared 5.9 percent year on year while non-food inflation edged up 1.1 percent in May.

On a month-on-month basis, the CPI dropped 0.5 percent in May, the NBS said.

Since January, CPI data has been calculated using a new comparison base that takes new products and services into consideration, reflecting a change in consumption patterns.

The adjustment slightly reduced the weight of food, which used to account for nearly one-third of the CPI calculation.