getting a date 25 years back

Hi there, I am trying to create a date which is 25 years back from today. The purpose of this is to be able to query a mysql database "date" field for columns smaller than this date. I tried this: $years = 25; $start_from = date("Y-m-d",strtotime("- ".$years." year")); Somehow it always ads the years instead of subtracting. Has anybody an idea on how to do that? Thank you in advance for any help, Merlin