Sales of new cars, trucks and buses in Japan were slightly lower in May 2003 than a year ago, mainly because of a sharp drop in demand for cheaper mini vehicles, according to a Reuters report. The news agency, citing data from industry groups, said total Japanese vehicle sales shrank 0.4% in May to 419,692 while sales of 660cc mini vehicles, which receive preferential tax treatment, fell 6% to 128,329 units for the second straight month of decline.