97% reliability? The world fleet reliability for B757s and B767s is 98.3% and 98.4% respectively, so 97% for an ancient old warbird is pretty good.
The commercial figures are supported by detailed reliability engineering data though and every flight is meticulously logged, none of this "62 give or take" stuff. Exactly how many formal bookings were there and how many no-shows - other than unavoidable due to weather?