Secondary data is the data that have been already collected by and readily available from other sources. Such data are cheaper and more quickly obtainable than the primary data and also may be available when primary data can not be obtained at all. Advantages of Secondary data.

The availability of secondary data is highly dependent on the primary researcher's decision to share their data publicly or not. An example of primary data is the national census data collected by the government while an example of secondary data is the data collected from online sources.

Advantages of Secondary Data 1 There is no issue of data collection as it is obtained by performing operations on primary data collected. 2 The cost involved in secondary data collection is relatively less. 3 Quality of data is not the responsibility of the investigator.