Remove the date of 17/2/2012 from country A

Hello,
i have recently faced a problem in excel. my problem is that i have three country data on daily basis. i want the same date will be appeared in each country.
e.g A country trade on 17/2/2012 but the B and C country no trade on the same date, i want to remove the date of 17/2/2012 from country A.
Please help me.