What is the difference between the RPI and CPI rate of inflation

Both the Consumer Price Index (CPI) and Retail Price Index (RPI) are ways of measuring inflation which is the average change in price of a basket of goods. The RPI, however, includes the costs of housing such as mortgage mortgage repayments, rent and council tax, which take up a large proportion of someone’s income. The CPI on the other hand does not include these goods and as a result is generally around 1% lower than the RPI. Both have their own merits but CPI is generally considered to be more accurate and is used internationally so it is more useful for comparisons.