Why need tables and charts? >As a general,appropriate tables and charts should be constructed whenever a set of data contains about 20 or more observations. >The important features or characteristics of the data from these tables and charts can be extracted Data are organized and presented in the form of tables and charts in order to enhance data analysis and interpretation Statistics for Managers Using Microsoft Excel Chap 2-3 Tongji University,School of Economics ManagementStatistics for Managers Using Microsoft Excel Chap 2-3 Tongji University, School of Economics & Management Why need tables and charts?  As a general, appropriate tables and charts should be constructed whenever a set of data contains about 20 or more observations.  The important features or characteristics of the data from these tables and charts can be extracted  Data are organized and presented in the form of tables and charts in order to enhance data analysis and interpretation