10,297 used the AMS service in September, this was the best month on the route since September 2008 when 10,589 passengers flew it. Based on 3 rows of business class (so 6 vacant seats), I would put the load factor at 72% last month.
So far this year, the route is 12% up on 2017 - this is despite the summer schedule being cut back due to slot restrictions at AMS when maintenance work was being done on the runway. 2018 should be the best numbers on this route since 2008.
As HWU said, we don't know the yield (and of course KLM are running bigger planes than 12 months ago so might have dropped prices slightly) but KLM do still charge a significant premium to fly from MME over NCL or LBA, especially on connecting flights.