I have a huge spreadsheet with simple data as follows
13:04:28 A 13:04:37 A 13:06:56 B 13:07:03 B 13:07:10 C 13:07:18 C 13:07:23 C 13:07:28 C 13:07:33 C
Basically timestamp,classification in two columns. i want to plot a pie chart showing the distribution of A,B and C etc by the number of times of their occurrence. How can I do so?