Python 2.7 shows 10,000 days.
>>> datetime(2011, 9, 30) - datetime(1984, 5, 14)
datetime.timedelta(10000) >>> datetime(2011, 9, 30) - datetime(1984, 5, 14)
datetime.timedelta(10000) irb(main):017:0> (Time.utc(2011, 9, 30) - Time.utc(1984, 5, 14)) / 60 / 60 / 24
=> 10000.0 echo date_diff(date_create('1984-05-14'), date_create('2011-09-30'))->format('%a days');
=> 10000 days