ATM figures given are not the actual true movements at Luton. According to the airports Annual Monitoring Report for 2014
Annual Monitoring Report - London Luton Airport Luton was handling even then 103,939 so for 2015 the figure is more likely to be around 125,000 movements.
79,171 passenger flights including commercial flights by executive aircraft.
17,369 non-commercial flights
5,704 positioning flight
1,695 cargo flights.
Of those non commercial flights
16,831 General Aviation private aircraft, helicopters and business jets not operating for hire or reward
347 Other
142 Test and training
47 Official
2 Military
So my understanding is that if a Biz jet is owned it is non-commercial but if it is hired it is commercial. As many bizjets at Luton will be classed as commercial an increase in that traffic will alter the passengers per aircraft figure so might not have any bearing on passengers passing though the terminal.
Commercial – operating for hire or reward and includes cargo, passenger and positioning flights
Non-Commercial – not operating for hire and reward
Cargo – aircraft movements which are solely for freight. It should be noted that freight can also be
carried on aircraft in other categories
General Aviation – private aircraft, helicopters and business jets not operating for hire or reward
Passenger – commercial passenger flights, including executive aircraft
Positioning – typically empty flights to/from other airports
Military – flights on military business
Official – flights solely for official purposes by British or foreign civil government departments
Other – other non-commercial movements, e.g. a departing aircraft that has made an unscheduled
return to base
Test & Training – training flights involving aircraft and also flights following or during aircraft
maintenance