Cost reduction still is the top challenge facing the automotive industry -- but emissions and safety regulations are gaining ground -- say designers and engineers. In the fifth annual Du Pont Automotive/Society of Automotive Engineers (SAE) survey of automotive engineers and designers, 31% of respondents identified cost reduction as the No. 1 challenge facing their profession. Another 13% chose emissions regulations as the top challenge; that's up 62% from last year. And 13% named safety regulations as the No. 1 challenge for their industry, up 50% over last year. The cost issue has topped the survey list for the last five years -- and the industry's corresponding concern has paid off for consumers. The purchase of an average-priced new vehicle last year took 24.6 weeks of median family pre-tax income, down 10% from two years ago, shows a recent Comerica Bank study The Du Pont survey subjects were automotive engineers and designers that attended the 1999 SAE International Congress and Exposition in Detroit last month.