December's flash consumer prices were unchanged in the final data, with the monthly reading rising 0.1 percent and the annual inflation remaining at November's 1.3 percent.

The stabilisation of yearly inflation underlines mixed trends, such as accelerating growth in the prices of regulated energy products (from 7.4 percent to 12.7 percent) and non-regulated energy products (from minus 6.6 percent to minus 4.2 percent), but slower growth in the prices of unprocessed food (from 3.8 percent to 2.3 percent) and services related to recreation including repair and personal care (from 3.7 percent to 3.1 percent).

Core inflation, excluding volatile items like energy and fresh food, was 1.8 percent, down from 1.9 percent in November. Excluding just energy, the rate was 1.7 percent, down from 2.0 percent in November.

The HICP, which, unlike the CPI, accounts for seasonal factors like summer sales, rose 0.1 percent monthly, also unchanged from the flash estimate. This trimmed the annual rate to 1.4 percent, down from November's 1.5 percent. In 2024 the annual rate of change of HICP was 1.1 percent on average compared to 5.9 percent seen in 2023.

The consumer price index (CPI) is a measure of the average price level of a fixed basket of goods and services purchased by consumers. Monthly and annual changes in the CPI provide widely used measures of inflation. A provisional estimate, with limited detail, is released about two weeks before the final data are reported.

The consumer price index is the most widely followed indicator of inflation. An investor who understands how inflation influences the markets will benefit over those investors that do not understand the impact. In countries such as the Italy where monetary policy decisions rest on the central bank's inflation target, the rate of inflation directly affects all interest rates charged to business and the consumer. As a member of the European Monetary Union, Italy's interest rates are set by the European Central Bank.

Italy like other EMU countries has both a national CPI and a harmonized index of consumer prices (HICP). Components and weights within the national CPI vary from other countries, reflecting national idiosyncrasies. The core CPI, which excludes fresh food, is usually the preferred indicator of short-term inflation pressures.

Inflation is an increase in the overall prices of goods and services. The relationship between inflation and interest rates is the key to understanding how indicators such as the CPI influence the markets - and your investments. As the rate of inflation changes and as expectations on inflation change, the markets adjust interest rates. The effect ripples across stocks, bonds, commodities, and your portfolio, often in a dramatic fashion.

By tracking inflation, whether high or low, rising or falling, investors can anticipate how different types of investments will perform. Over the long run, the bond market will rally (fall) when increases in the CPI are small (large). The equity market rallies with the bond market because low inflation promises low interest rates and is good for profits.