The Commerce Ministry has adjusted the base year in calculating the consumer price index (CPI), a gauge of headline inflation, starting with January's figures to keep pace with changing social and economic conditions.
According to Pimchanok Pitfield, director-general of the Trade Policy and Strategy Office under the Commerce Ministry, the ministry will start applying 2019 as the base year, which was the year the National Statistical Office of Thailand used to complete its survey on national economic and social conditions. It was also the last full year in which Thailand was not affected by the Covid-19 outbreak.
The previous base year was 2015.
The base-year adjustment is being applied starting with this month's figures and will continue to be applied going forward.
The ministry normally adjusts the base year for the CPI calculation every 4-5 years, she said.
Mrs Pimchanok said the new CPI calculation extends its coverage to households with a monthly income of 6,987-50,586 baht per household, which represents 71% of households nationwide.
The previous range was 12,000-62,000 baht per household per month, or 29% of households nationwide.
The ratio of households in Greater Bangkok has also been reduced to 22% from 42% under the previous calculation.
The number of product and service items used in the CPI calculation has been expanded to 430 from 422 items previously, comprising 341 product items and 89 services.
New products and services added include medical face masks, cereal grains, hair colour products, pet grooming services, fire insurance premiums, carminatives, balm and cordials.
She said the ministry now applies a new definition for low-income earners. It sets the income level at no more than 100,000 baht per year per household, or 8,333 baht per person per month.
The previous definition varied depending on the location and province.