--Once a year, at Xmas-New Year's, the Economist does a 2-week issue.
--For those who can't read the article, it doesn't say that much: just that the number of miles is growing a lost faster than the number of seats/flights, and therefore inflation is resulting (modestly now as award flights become harder to get or effectively cost more miles; more dramatically, goes the prediction, in the future.
--They said this before some years ago, and the sky is still up there.
--But my personal philosophy, not necessary good for anyone else, is carpe diem, and I try to spend my miles about as fast as I get them.