"R0 F8 A7 J9 C9 D9 I9 W5 T5 Y9 B9 K9 M9 L9 V9 S9 N9 Q9 O9"
They are often referred to as "Fare Bucket" codes.
This is how the Majority of airlines show fare availability for a flight.
The Alphabetic characters represent "fare bucket" codes and the numbers adjacent to each represent the minimum number of seats in that fare bucket an airline is prepared to sell for a particular flight at the time of query. They do not add together to show the total number of available seats.
Now with the numbers, in order the keep competitors somewhat in the dark as to how many seats are actually available, the airlines have their own determined maximum number to reveal at any one time.
For QF it's generally 9, for AA it's 7 and for JQ, 4.
As a general rule of thumb, the letters indicate availability in a descending cost order from left to right.
The following relates to Qantas. Different airlines employ different letters for various fares/cabins.
R0 F8 A7: First Class - Qantas are willing to sell up to 8 seats in the Fist Class cabin. This at either the full rate (F) or discounted (A), none at the Premium (R) rate. This does not mean that there are 15 seats available. Note that currently, Qantas First class cabins have 14 'seats'. What would normally happen if someone booked on the flight into one of these code is that both numbers would reduce, i.e. it goes to F8 A6.
J9 C9 D9 I9: Business class - At least nine are up for sale at the Full (J) rate, Discounted (C), more discounted (D) and at the deep discount rate (I) - generally means slow business class sales.
W5 T5: Premium Economy - Qantas are willing to only sell up to 5 PE seats.
Y9 B9 K9 M9 L9 V9 S9 N9 Q9 O9: Economy These are the WHY rates and there are probably plenty of seats for sale, including deep discount (N, Q, O).
