Airfares notched lower and demand slackened in September, curbing revenue and profits for discount flyer Southwest Airlines (LUV). Adjusted earnings per share slipped 13% to 13 cents, matching analysts' expectations. Revenue of $4.3 billion was just under analyst forecasts. Fuel costs slipped 3.7%, but overall operating expenses climbed 4.2%, with maintenance costs up 10%, and salaries and wages up 4%. Southwest shares edged up 0.5% in midday