Hello Everyone

Please I need major help!

I want to lookup which period we are in based on today's date. The data below is the period dates. I then want to creat a vertical line for that period in an excel chart. Can this be done? thanks in advance

P1 01/04/2009 30/04/2009
P2 01/05/2009 31/05/2009
P3 01/06/2009 30/06/2009
P4 01/07/2009 31/07/2009
P5 01/08/2009 31/08/2009
P6 01/09/2009 30/12/2009