perhaps this has been said somewhere in this thread....if so i apologise for the repeat...

the biggest devaluation in miles is the cheaper fares currently available...20-25 years ago, an advance purchase ticket to many us cities was around $500 in y, while a walk up was around $1000, so roughly, 25k mi's was worth 2cts on an advance purchase & 4cts on a walk up, and saturday nite stays were required for the cheaper fares...in those days, the senior coupon packs @ $300 were a good deal plus could be used for standby and sat nite stay wasn't required...recently, i got a tue-thur [same week] coach ticket for my wife dfw-lga for $225 all in which would be less than 1ct/mi on an award plus maybe an expedite fee.

traditionally, i would use mi's for last minute tickets for family and for long haul upgrades, valueing the mi's at the net cost saving, which i believe is realistic even though i probably wouldn't pay for j [except for my wife who won't go on long hauls in y, which fortunatly, i haven't had to do].

anyway, i believe that lower fares are responsible for considerable mi devaluation, particularly for people that use them for domestic trips..