This is why the one day per month in version 7.0 was such a great idea. Micro-scale stuff (train movements) can happen correctly as measured by the clock in hours or minutes, while macro-scale stuff (economics) can happen correctly as measured by the clock in months. It lets the different time scales exist harmoniously. Perhaps it would be a good idea to be able to change the number of days per month or months per day, but 1 works reasonably. I'm disappointed that this feature disappeared in 7.1.
Edit by jamespetts: Split from Time scale vs. truck movements (http://forum.simutrans.com/index.php?topic=4168.0) because this is a different subject.
Blaine,
I am confused - I have not changed any timing related systems between 7.0 and 7.1.
At one point, I had a simutrans experimental version labeled 7.0 which had a clock which showed 1 day per month, or rather the clock did not show which day it was and changed the month after each day completed. Unfortunately, at this point, I don't remember exactly where it got it from. Judging by your response, apparently that wasn't your official release. In any case, I still feel that allowing the number of days per month to be arbitrary is a great way to reconcile the micro and marco time scales in a way that can be easily understood.
One can specify different timing options in simuconf.tab in both Simutrans-Experimental and Simutrans-Standard. Perhaps you just happened to install it with a modified simuconf.tab?