Caltex Australia Limited has announced a significantly improved result with net full year profit after tax of A$215.2 million, or 79.7 cents a share, for 2002, compared with a net loss after tax of A$186.1 million or Ð69 cents a share in 2001. (US$1=A$1.7). Caltex Chairman Dick Warburton said that even though rising crude oil…