The Consumer Price Index measures the average change over time in the prices paid by urban consumers for a market basket of consumer goods and services. If you are looking to open a file related to CPI data, it could be in a format like CSV, Excel, or a specialized file format used by statistical software. In this case, you would typically use a program like Microsoft Excel, Google Sheets, or statistical software like R or Python with libraries like pandas to open and analyze the data. https://cruxtekk.com/what-are-cpi-files-how-to-open-a-cpi-file/