CREATE TABLE table_64743 ("Rank" FLOAT, "Name" TEXT, "Height ft  (  m  ) " TEXT, "Floors" FLOAT, "Year" FLOAT)

What is the lowest rank for El Paso Natural Gas Company Building?
SELECT MIN("Rank") FROM table_64743 WHERE "Name" = 'el paso natural gas company building'
SELECT MIN("Rank") FROM "table_64743" WHERE "Name" = 'el paso natural gas company building'