TOKYO, June 25 (Xinhua) -- Consumer prices in Japan, excluding volatile fresh food, fell 1.2 percent in May from a year earlier marking the 15th straight month of decline, the Ministry of Internal Affairs and Communications said in a preliminary report on Friday.

The core consumer price index (CPI) stood at 99.3 against the base of 100 for 2005 and May's reduction was in line with analysts expectations for a 1.3 percent drop.

Additionally, the core CPI for Tokyo's 23 wards in June fell 1. 3 percent from a year earlier, the ministry said, matching forecasts for a 1.4 percent decline following the 1.6 percent decline logged in May.

Consumer price index measures a price change for a constant market basket of goods and services from one period to the next within the same area. The percent change in the CPI is a measure estimating inflation.

Specifically the CPI data for Tokyo is considered by economists as a key gauge for the nation's core inflation trend.