Q.What is secondary data?

Secondary data is pre-existing data collected by someone else, reused for a new investigation.

Unlike primary data (collected first-hand by the investigator for the specific purpose at hand), secondary data has already been collected, compiled and often published by another agency — e.g. government reports (Census, NSSO), international bodies (World Bank, UN), newspapers, or earlier research studies. Because it was originally gathered for a different purpose, a user of secondary data must critically exa …