Which of the following statements is correct with regard to Consumer Price Index?
1. It measures the average change in the sale price of goods and services either as they leave the place of production or as they enter the place of production.
2. It is used to monitor changes in the cost of living over time.
3. It is used to monitor the cost of the goods and services bought by producers and firms.
4. It reflects the price of all the goods and services produced domestically.