Simplify the following text for a Grade 9 native English-speaking person.
Original: Officially released on 9 April , the stamp shows the roughly one-year-old Knut with the slogan `` Natur weltweit bewahren '' ( `` Preserve nature worldwide '' ) .
Simplified: The stamp shows the roughly one-year-old Knut with the slogan `` Natur weltweit bewahren '' ( `` Preserve nature worldwide '' ) .