How many movies have Takaaki Yamashita and Yoko Sato collaborated on?

They have worked on 4 movies together! Their first movie together was Hell Teacher Nube: At 0 a.m. Nube is Dead!! (1997) while their highest rated movie together was Interstella 5555: The 5tory of the 5ecret 5tar 5ystem (2003). They have not worked together since One Piece: Baron Omatsuri and the Secret Island (2005). They are most known for their animation films together.