What OS and FM versions are involved? I once saw this some years ago when a computer's System settings were changed for how numbers were to be displayed by default, and, in that case, correcting the OS preferences/settings fixed it. I don't know if that's what's going on for you, but that's the only time I've seen something like what you described.
Yes, you could have also have changed the defaults for the file.... but that wouldn't have changed existing field settings.
When you change settings with nothing selected you are changing defaults.
Thanks, Stephen and Lyndsay, for the help.
I'm using FMPA11.03, and a a mixture of Windows (7) and OS X (10.7.5). There doesn't appear to be anything odd about the system settings on either machine. One other characteristic that I've noticed is that although the formats have changed to currency, the symbol used is the hash, rather than "£". I'm adamant that I haven't changed the format of the actual fields on the layouts, but can't be so sure that I didn't inadvertently change the default settings. That said, I couldn't have changed the curency symbol to hash, as I can't even find it!
All very peculiar. I guess I'll just have to put all the layouts right, then hope that the changes stick.