Better Performance: Major airlines showed an improvement in the number of flight delays and baggage problems reported in January, the Department of Transportation said. The 13 largest domestic carriers reported that 76.7% of their flights operated on time in January, compared to the 76.1% on-time performance in December, 1988, and the 69.2% of January, 1988. Mishandled baggage reports averaged 7.86 per 1,000 passengers in January, compared to 8.58 per 1,000 in December, 1988. However, consumer complaints filed with the department against the industry increased in February to 1,138, compared to 1,086 in January. Still, the February, 1989, total was a 51% decline over a year ago when complaints reached 2,308.