in march 1993 the city produced its own ev operating manual and in october 1993 , osaka 's prefectural government announced a tentative plan that proposes obtaining low-pollution vehicles , including evs , for official use to reduce nitrogen oxide -lrb- n0x -rrb- pollution levels by approximately 30 percent by fiscal year 2000 -lrb- asahi shimbun 27 oct 93 -rrb- .