It doesn't matter when CC was installed, it only matters when listeners were tuned in -- were listeners tuned in to the station more than 24hr prior to now? If not, they won't show up until the next statistics update.
If you've had more than 24hr of listener data prior to now, then something is up. In that case, I'd guess that your cron job isn't running for some reason -- make sure that cron isn't having issues. (If you have a bad line in /etc/crontab it can kill ALL the cron jobs configured after the bad line, even ones which aren't related to the bad line, like Centova Cast.)
If that yields nothing, then run the statistics job manually and look for errors:
/usr/local/centovacast/bin/ccmanage processlogs all --debug