In this industry that usually translates to "All of us are broke" but I don't know enough about the four of them to know of that applies here as well.
Well...Benny and Bjorn are quite wealthy from, among other things, royalties from Mamma Mia and the recent resurgence in interest in ABBA, and Frida (Her Serene Highness) is married to a Prince. Don't know about Agnetha though.
The most interesting thing about this is that, if, in the mid-80s or so, a bunch of 70 year old singers were reuniting to produce no music, absolutely no one under the age of 60 would have given a shit.