Create formula for Previous Year:  ToText(Year(CurrentDate)-1,0,"")
Place this formula in Page Header section over the column to represent previous year.

Create formula for Current Year: ToText(Year(CurrentDate),0,"")
Place this formula in Page Header section over the column to represent current year.

An example of creating a dynamic column label formula for a Fiscal Year ( ex 7/1/2010 - 6/30/2011 -> 2010 - 2011):
Date Header1_A:
if CurrentDate in Date(Year(CurrentDate)-1,6,30) to Date(Year(CurrentDate),7,1) then Year(CurrentDate)-1

Date Header1_B:
if CurrentDate in Date(Year(CurrentDate)-1,6,30) to Date(Year(CurrentDate),7,1) then Year(CurrentDate)