Cpi: the consumer price index is used to monitor changes in the cost of living over ime. When the consumer price index rises, the typical family has to spend more dollars to maintain the same standard of living. It is the overall measure of the cost of the goods and services bought by a typical consumer. Economists use the term inlaion to describe a situaion in which the economy"s overall price level is rising. The inlaion rate is the percentage change in the price level from the previous period. The upward change in terms of the price level going up and up. In canada, stats canada computes and reports cpi every month. Five steps: determine the basket, find the prices, compute the basket"s cost, choose a base year and compute the index, compute the inlaion rate. In terms of gdp accouning, when you buy a new house your mortgage is consumpion and is therefore in the category of shelter.