What does the price index 102 stand for?

It has increased by 2%. The price index 102 means that the benchmark period or value of the index has increased by 2%, and the benchmark value of the index is 100, so the price index 102 means that the current price level has increased by 2 percentage points compared with the benchmark period. Price index is a relative index, which is used to measure the price change of a group of goods or services and reflect the degree of inflation or deflation.