Lufthansa reported a 4.3 percent increase in sales on the passenger side in June but was unable to sell the extra freight space it offered during the month, it said in its monthly traffic report. Global air freight demand has been slowing in recent months as economies stutter, after a promising start to the year, figures from air industry association IATA show. Lufthansa said that in June freight capacity at its Lufthansa Cargo unit rose by 2.9 percent, driven by space in the bellies of its passenger planes, but sales dropped by 0.9 percent. Cargo load factors, or how full its planes are, dropped 2.5 percentage points.