Date function that compare 2 date in single column and return value

Hi

How to write simple date function that will compare 2 date in single column and then will return statement "write off" or "still use" if it meet the condition

example

Column A Column B
12/07/2005 Write Off
12/07/2012 still use



from example if in date column a is more than the today date, it will automatic show in column B write off else if less than today it will show still in use. This date comparison is to check if the date at column A is more than 2 years or less. This is for inventory system that see if the item is more than or reach 2 years, it will show write off or if less than 2 years, it will show still use


thanks
abu