score:12
tl;dr: Fares are typically adjusted on major routes every few days to every few weeks.
I assume you already know a little about how airline price calculation works, but if you do not, you may want to take a look at an admittedly rather lengthy answer I wrote describing the interplay between fares and availability.
Airline fare tariffs are distributed by two companies, ATPCO (the Airline Tariff Publishing Company) and SITA. ATPCO is by far the more important company by volume, and is owned by a conglomeration of airlines. Every network airline has to file its fare tariff on each city pair with at least one of these companies. ATPCO and SITA, in turn, distribute the fare tariffs to GDSes, global distribution systems, which pass on the information to travel agents and other airlines.
ATPCO distributes fare tariffs once per hour, every hour, except on Sundays when it updates only a few times per day. It often takes many hours for an unexpected fare change to make its way through the many layers of cacheing down to a website front end, which is why error fares, pulled abruptly by revenue management, are difficult for airlines to make unavailable immediately, and remain as ghost fares on some websites long after they cease to be ticketable.
As a random example, BA's cheapest fare on London-San Francisco was last modified ten days ago (see the bottom line of the fare summary for the publication date):
V FARE BASIS BK FARE TRAVEL-TICKET AP MINMAX RTG
1 OJN5S4Z1 OR 300.00 ---- 50/3 SU/12M AT01
PASSENGER TYPE-ADT AUTO PRICE-YES
FROM-LON TO-SFO CXR-BA TVL-28OCT16 RULE-J678 IPRA/1
FARE BASIS-OJN5S4Z1 SPECIAL FARE DIS-E VENDOR-ATP
FARE TYPE-XPX RT-INSTANT PURCHASE FARE
GBP 246.00 MPM E19OCT16 D-INFINITY FC-OJN5S4Z1 FN-6I
SYSTEM DATES - CREATED 18OCT16/1218 EXPIRES INFINITY
In fact, inspection of the historical tariff on the 17th October, shows that this particular fare didn't exist on that day.
But Qantas's lowest public return fare on Hong Kong-Sydney hasn't been touched since April.
V FARE BASIS BK FARE TRAVEL-TICKET AP MINMAX RTG
1 SSHK3 S R 767.00 ---- -/ -/ 3M EH01
PASSENGER TYPE-ADT AUTO PRICE-YES
FROM-HKG TO-SYD CXR-QF TVL-28OCT16 RULE-7180 IPRPG/8
FARE BASIS-SSHK3 SPECIAL FARE DIS-E VENDOR-ATP
FARE TYPE-XEX RT-REGULAR EXCURSION
HKD 5950 7180 E04APR16 D-INFINITY FC-SSHK3 FN-
SYSTEM DATES - CREATED 03APR16/2114 EXPIRES INFINITY
[Note, that this doesn't necessarily represent the lowest fare Qantas has offered on the city pair since April. It may have filed a lower fare that has since expired. But this fare was available at this price, even if it was hidden by a lower-priced fare in the same bucket.]
Air France has consistently offered the same business class fare, ZLSFR
, on Paris-Johannasburg, for nearly a year.
V FARE BASIS BK FARE TRAVEL-TICKET AP MINMAX RTG
1 ZLSFR Z R 3312.00 ---- 28 7/12M EH01
PASSENGER TYPE-ADT AUTO PRICE-YES
FROM-PAR TO-JNB CXR-AF TVL-28OCT16 RULE-FRLS IPREUAF/23
FARE BASIS-ZLSFR SPECIAL FARE DIS-E VENDOR-ATP
FARE TYPE-BAP RT-BUSINESS CLASS ADVANCE PURCHASE
EUR 3044.00 0023 E25NOV15 D-INFINITY FC-ZLSFR FN-
SYSTEM DATES - CREATED 24NOV15/0221 EXPIRES INFINITY
However, AA tweaked its ONE7F0G1
fare on Amsterdam-Sรฃo Paulo only a couple of days ago.
V FARE BASIS BK FARE TRAVEL-TICKET AP MINMAX RTG
1 ONE7F0G1 O R 299.00 R31MR T01NV 7/3 SU/ 30 AT01
PASSENGER TYPE-ADT AUTO PRICE-YES
FROM-AMS TO-SAO CXR-AA TVL-28OCT16 RULE-A099 IPRSAA2/27
FARE BASIS-ONE7F0G1 SPECIAL FARE DIS-E VENDOR-ATP
FARE TYPE-XPN RT-INSTANT PURCHASE NONREFUNDABLE-TYPE FARES
EUR 275.00 MPM E27OCT16 D31MAR17 FC-ONE7F0G1 FN-R
SYSTEM DATES - CREATED 26OCT16/1119 EXPIRES INFINITY
You can see that in general, changing the tariff is not a good way to make immediate changes, but the tariff is nonetheless kept under constant watch.
This system does not lend itself to rapid price alterations. Instead day-to-day or minute-by-minute price alterations are managed by publishing numerous fares in advance and controlling availability by restricting the booking classes on individual flights. The availability can indeed be changed in real time.
If they only modify availability, are minimum and maximum fares a good indicator of how much a fare can fluctuate?
The most complete indicator is direct inspection of the tariff. However, it doesn't really tell you that much, because the airlines deliberately leave the options on the table. For example, I give the tariff between Edinburgh and Cairns, as published by BA.
Fare Basis Airline Booking Trip Type Fare Cabin Effective Expiration Min/Max Advanced
Class Date Date Stay Purchase Req
OLRC1UK BA O Round-Trip 202.00 (GBP) E 01/11/16 08/12/16 SU / 12M 07
07/02/17 29/03/17
OKRC1UK BA O Round-Trip 222.00 (GBP) E 08/04/17 30/06/17 SU / 12M 07
QLRC1UK BA Q Round-Trip 242.00 (GBP) E 01/11/16 08/12/16 SU / 12M
07/02/17 29/03/17
QKRC1UK BA Q Round-Trip 262.00 (GBP) E 08/04/17 30/06/17 SU / 12M
OLRC1UK BA O Round-Trip 317.00 (GBP) E 01/11/16 08/12/16 SU / 12M 07
07/02/17 29/03/17
OKRC1UK BA O Round-Trip 337.00 (GBP) E 08/04/17 30/06/17 SU / 12M 07
OJRC1UK BA O Round-Trip 352.00 (GBP) E 04/10/16 31/10/16 SU / 12M 07
01/01/17 06/02/17
QLRC1UK BA Q Round-Trip 357.00 (GBP) E 01/11/16 08/12/16 SU / 12M
07/02/17 29/03/17
QKRC1UK BA Q Round-Trip 377.00 (GBP) E 08/04/17 30/06/17 SU / 12M
QJRC1UK BA Q Round-Trip 392.00 (GBP) E 04/10/16 31/10/16 SU / 12M
01/01/17 06/02/17
SLBBGB BA S Round-Trip 440.00 (GBP) E 01/11/15 30/11/16 SU / 12M
09/04/17 29/06/17
OJRC1UK BA O Round-Trip 467.00 (GBP) E 04/10/16 31/10/16 SU / 12M 07
01/01/17 06/02/17
QJRC1UK BA Q Round-Trip 507.00 (GBP) E 04/10/16 31/10/16 SU / 12M
01/01/17 06/02/17
MLBBGB BA M Round-Trip 550.00 (GBP) E 01/11/15 30/11/16 SU / 12M
09/04/17 29/06/17
SLBBGB BA S Round-Trip 555.00 (GBP) E 01/11/15 30/11/16 SU / 12M
09/04/17 29/06/17
MLBBGB BA M Round-Trip 665.00 (GBP) E 01/11/15 30/11/16 SU / 12M
09/04/17 29/06/17
KLBBGB BA K Round-Trip 670.00 (GBP) E 01/11/15 30/11/16 SU / 12M
09/04/17 29/06/17
SJBBGB BA S Round-Trip 710.00 (GBP) E 01/12/15 07/12/16 SU / 12M
30/12/15 08/04/17
11/08/16 31/10/16
30/06/17 15/07/17
KLBBGB BA K Round-Trip 785.00 (GBP) E 01/11/15 30/11/16 SU / 12M
09/04/17 29/06/17
HLBBGB BA H Round-Trip 800.00 (GBP) E 01/11/15 30/11/16 SU / 12M
09/04/17 29/06/17
SJBBGB BA S Round-Trip 825.00 (GBP) E 01/12/15 07/12/16 SU / 12M
30/12/15 08/04/17
11/08/16 31/10/16
30/06/17 15/07/17
MJBBGB BA M Round-Trip 830.00 (GBP) E 01/12/15 07/12/16 SU / 12M
30/12/15 08/04/17
11/08/16 31/10/16
30/06/17 15/07/17
HLBBGB BA H Round-Trip 915.00 (GBP) E 01/11/15 30/11/16 SU / 12M
09/04/17 29/06/17
SHBBGB BA S Round-Trip 920.00 (GBP) E 08/12/15 29/12/16 SU / 12M
16/07/17 10/08/17
MJBBGB BA M Round-Trip 945.00 (GBP) E 01/12/15 07/12/16 SU / 12M
30/12/15 08/04/17
11/08/16 31/10/16
30/06/17 15/07/17
BLBBGB BA B Round-Trip 970.00 (GBP) E 01/11/15 30/11/16 SU / 12M
09/04/17 29/06/17
KJBBGB BA K Round-Trip 1010.00 (GBP) E 01/12/15 07/12/16 SU / 12M
30/12/15 08/04/17
11/08/16 31/10/16
30/06/17 15/07/17
SHBBGB BA S Round-Trip 1035.00 (GBP) E 08/12/15 29/12/16 SU / 12M
16/07/17 10/08/17
MHBBGB BA M Round-Trip 1060.00 (GBP) E 08/12/15 29/12/16 SU / 12M
16/07/17 10/08/17
BLBBGB BA B Round-Trip 1085.00 (GBP) E 01/11/15 30/11/16 SU / 12M
09/04/17 29/06/17
KJBBGB BA K Round-Trip 1125.00 (GBP) E 01/12/15 07/12/16 SU / 12M
30/12/15 08/04/17
11/08/16 31/10/16
30/06/17 15/07/17
MHBBGB BA M Round-Trip 1175.00 (GBP) E 08/12/15 29/12/16 SU / 12M
16/07/17 10/08/17
HJBBGB BA H Round-Trip 1210.00 (GBP) E 01/12/15 07/12/16 SU / 12M
30/12/15 08/04/17
11/08/16 31/10/16
30/06/17 15/07/17
KHBBGB BA K Round-Trip 1250.00 (GBP) E 08/12/15 29/12/16 SU / 12M
16/07/17 10/08/17
TLAP1UK BA T Round-Trip 1260.00 (GBP) E 01/11/16 08/12/16 SU / 12M 07
01/01/17 29/03/17
26/04/17 30/06/17
HJBBGB BA H Round-Trip 1325.00 (GBP) E 01/12/15 07/12/16 SU / 12M
30/12/15 08/04/17
11/08/16 31/10/16
30/06/17 15/07/17
TJAP1UK BA T Round-Trip 1346.00 (GBP) E 11/08/16 31/10/16 SU / 12M 07
KHBBGB BA K Round-Trip 1365.00 (GBP) E 08/12/15 29/12/16 SU / 12M
16/07/17 10/08/17
TLAP1UK BA T Round-Trip 1375.00 (GBP) E 01/11/16 08/12/16 SU / 12M 07
01/01/17 29/03/17
26/04/17 30/06/17
BJBBGB BA B Round-Trip 1450.00 (GBP) E 01/12/15 07/12/16 SU / 12M
30/12/15 08/04/17
11/08/16 31/10/16
30/06/17 15/07/17
HHBBGB BA H Round-Trip 1450.00 (GBP) E 08/12/15 29/12/16 SU / 12M
16/07/17 10/08/17
TJAP1UK BA T Round-Trip 1461.00 (GBP) E 11/08/16 31/10/16 SU / 12M 07
TLBBGB BA T Round-Trip 1544.00 (GBP) E 01/11/15 30/11/16 SU / -- 07
09/04/17 29/06/17
BJBBGB BA B Round-Trip 1565.00 (GBP) E 01/12/15 07/12/16 SU / 12M
30/12/15 08/04/17
11/08/16 31/10/16
30/06/17 15/07/17
HHBBGB BA H Round-Trip 1565.00 (GBP) E 08/12/15 29/12/16 SU / 12M
16/07/17 10/08/17
TLBBGB BA T Round-Trip 1659.00 (GBP) E 01/11/15 30/11/16 SU / -- 07
09/04/17 29/06/17
BHBBGB BA B Round-Trip 1690.00 (GBP) E 08/12/15 29/12/16 SU / 12M
16/07/17 10/08/17
BHBBGB BA B Round-Trip 1805.00 (GBP) E 08/12/15 29/12/16 SU / 12M
16/07/17 10/08/17
ELBBGB BA E Round-Trip 1844.00 (GBP) E 01/11/15 30/11/16 SU / -- 07
09/04/17 29/06/17
TJBBGB BA T Round-Trip 1934.00 (GBP) E 01/12/15 07/12/16 SU / -- 07
30/12/15 08/04/17
11/08/16 31/10/16
30/06/17 15/07/17
ELBBGB BA E Round-Trip 1959.00 (GBP) E 01/11/15 30/11/16 SU / -- 07
09/04/17 29/06/17
TJBBGB BA T Round-Trip 2049.00 (GBP) E 01/12/15 07/12/16 SU / -- 07
30/12/15 08/04/17
11/08/16 31/10/16
30/06/17 15/07/17
EJBBGB BA E Round-Trip 2234.00 (GBP) E 01/12/15 07/12/16 SU / -- 07
30/12/15 08/04/17
11/08/16 31/10/16
30/06/17 15/07/17
THBBGB BA T Round-Trip 2280.00 (GBP) E 08/12/15 29/12/16 SU / -- 07
16/07/17 10/08/17
Y2BA BA Y Round-Trip 2344.00 (GBP) E -- / 12M
EJBBGB BA E Round-Trip 2349.00 (GBP) E 01/12/15 07/12/16 SU / -- 07
30/12/15 08/04/17
11/08/16 31/10/16
30/06/17 15/07/17
THBBGB BA T Round-Trip 2395.00 (GBP) E 08/12/15 29/12/16 SU / -- 07
16/07/17 10/08/17
Y2BA BA Y Round-Trip 2459.00 (GBP) E -- / 12M
EHBBGB BA E Round-Trip 2580.00 (GBP) E 08/12/15 29/12/16 SU / -- 07
16/07/17 10/08/17
EHBBGB BA E Round-Trip 2695.00 (GBP) E 08/12/15 29/12/16 SU / -- 07
16/07/17 10/08/17
IN4SUKP BA I Round-Trip 3057.00 (GBP) B SU / 12M 14
W2BA BA W Round-Trip 3142.00 (GBP) PE -- / 12M
W2BA BA W Round-Trip 3257.00 (GBP) PE -- / 12M
IN4SUKP BA I Round-Trip 3269.00 (GBP) B SU / 12M 14
YRT BA Y Round-Trip 3372.00 (GBP) E -- / 12M
IAP7 BA I Round-Trip 3734.00 (GBP) B SU / 12M 28
IAP7 BA I Round-Trip 3946.00 (GBP) B SU / 12M 28
AN5SUKP BA A Round-Trip 4177.00 (GBP) F SU / 12M 50
AN5SUKP BA A Round-Trip 4389.00 (GBP) F SU / 12M 50
W1RT BA W Round-Trip 4488.00 (GBP) PE -- / 12M
IAP7 BA I Round-Trip 4534.00 (GBP) B SU / 12M 28
IAP7 BA I Round-Trip 4746.00 (GBP) B SU / 12M 28
AAPGB BA A Round-Trip 5034.00 (GBP) F SU / 12M 28
AUPEGBR4 BA A Round-Trip 5184.00 (GBP) F -- / 12M
RAP1 BA R Round-Trip 5184.00 (GBP) B -- / 12M
RUPEGBR4 BA R Round-Trip 5184.00 (GBP) B -- / 12M
AAPGB BA A Round-Trip 5246.00 (GBP) F SU / 12M 28
AUPEGBR4 BA A Round-Trip 5396.00 (GBP) F -- / 12M
RAP1 BA R Round-Trip 5396.00 (GBP) B -- / 12M
RUPEGBR4 BA R Round-Trip 5396.00 (GBP) B -- / 12M
AAPGB8 BA A Round-Trip 5510.00 (GBP) F -- / 12M 28
AAPGB8 BA A Round-Trip 5722.00 (GBP) F -- / 12M 28
AUPEGBR3 BA A Round-Trip 5784.00 (GBP) F -- / 12M
D2BA BA D Round-Trip 5784.00 (GBP) B -- / 12M
DUPEGBR3 BA D Round-Trip 5784.00 (GBP) B -- / 12M
AUPEGBR3 BA A Round-Trip 5996.00 (GBP) F -- / 12M
D2BA BA D Round-Trip 5996.00 (GBP) B -- / 12M
DUPEGBR3 BA D Round-Trip 5996.00 (GBP) B -- / 12M
AUPEGBR2 BA A Round-Trip 6484.00 (GBP) F -- / 12M
C2BA BA C Round-Trip 6484.00 (GBP) B -- / 12M
CUPEGBR2 BA C Round-Trip 6484.00 (GBP) B -- / 12M
AUPEGBR2 BA A Round-Trip 6696.00 (GBP) F -- / 12M
C2BA BA C Round-Trip 6696.00 (GBP) B -- / 12M
CUPEGBR2 BA C Round-Trip 6696.00 (GBP) B -- / 12M
AAPGB7 BA A Round-Trip 6946.00 (GBP) F -- / 12M 07
AAPGB7 BA A Round-Trip 7158.00 (GBP) F -- / 12M 07
AUPEGBR1 BA A Round-Trip 8379.00 (GBP) F -- / 12M
J2BA BA J Round-Trip 8379.00 (GBP) B -- / 12M
JUPEGBR1 BA J Round-Trip 8379.00 (GBP) B -- / 12M
AUPEGBR1 BA A Round-Trip 8591.00 (GBP) F -- / 12M
J2BA BA J Round-Trip 8591.00 (GBP) B -- / 12M
JUPEGBR1 BA J Round-Trip 8591.00 (GBP) B -- / 12M
F2BA1 BA F Round-Trip 9862.00 (GBP) F -- / 12M
F2BA1 BA F Round-Trip 10074.00 (GBP) F -- / 12M
J1RT BA J Round-Trip 11694.00 (GBP) B -- / 12M
F1RT BA F Round-Trip 13772.00 (GBP) F -- / 12M
You can see that there is a wide range, from the good deal to the utterly ridiculous, of possible prices that might be on sale at any given time.
Upvote:-3
Well, here we go again...the answer is yes, but what they don't say or is hard to figure out unless you work in their pricing group is exactly how much and how often. As noted by Calchas, you can subscribe to a service that distributes fares.
The price fluctuation most people see are just a result of inventory depletion or expiration. Meaning the prices were determined some time before and the inventory (Q, R, N...) just sells or expires out so the next lowest price is returned. If they did their job, the prices shouldn't change at all.
If you're looking for an upper bound, Y/J/F are the ones to check.
Many sites, Kayak for instance, have a prediction feature.
I've never tried this but you might be able to gauge the price of future availability by trying book with certain inventory codes. The thing is, they might not be technically 'available' until others are gone.
BTW, fares aren't really 'filed' at least here in the US. Many stats are reported but they're not really held to anything.