hi Upendra,
Use the below method
pick(wildmatch(Year,2000, 2001,2002,'*'),'A', 'B', 'C', 'Other')
where Year is the field name. if the value is 2000 it will display A and so on....
You will find more explanation in the below forum
http://community.qlik.com/forums/t/39864.aspx