BEIJING, June 22 -- China will add two new indexes to its official economic data release calendar, measuring the performance of its brick-and-mortar retail industry quarterly, an official said Thursday.

The indexes - China's shopping mall composite index and convenience store business index - will be released by the Ministry of Commerce in the first month of each quarter, Sun Jiwen, the ministry spokesperson, said at a press conference.

The shopping mall composite index, composed by the China Chain-store &Franchise Association (CCFA) will survey 100 shopping malls in 58 cities nationwide, measuring leasing activity, operating costs and development prospects, Sun said.

The convenience store business index is based on a survey of 58 convenience store operators registered under the CCFA.

A reading above 50 indicates expansion while that below 50 suggests contraction.

Sun said the shopping mall composite index stood at 67.2 for the whole year of 2016 while the convenience store business index was 72.2 for the first quarter, both above the boom-or-bust threshold.

Consumption has become a strong engine driving China's economic growth, with the brick-and-mortar retail sector continuing to expand, Sun said.

Consumption contributed 77.2 percent of GDP growth in the first quarter this year, compared to 64.6 percent in 2016.

China's economy grew 6.9 percent year on year in the first quarter, the fastest pace since the third quarter of 2015.