Bear in mind also that "booked load factor" is not the same as "flown load factor". Ryanair (bless them) when talking about load factors always quotes something called "earned load factor", i.e. the % of seats which would be occupied if everyone who'd bought a ticket turned up (same as what is normally known as "booked load factor"). Obviously this considerably flatters their load factor number. Most other airlines (network airlines at least) would cite flown load factor, not booked load factor, when quoting a load factor figure.
(And just to be pedantic - we are talking about passenger load factor only, i.e. cabin factor. The load factor calculation is sometimes done for both passengers and cargo, so if the 747's passenger cabin is 75% full and its cargo hold is 60% full, the overall load factor is... well, you get the idea. But almost all of the time that load factor is referred to these days it means passenger load factor.)