I get the following domain age for martin-thoma.com in my dashboard (SEO Rankings):
Domain Age
365 days -8762 hours
The domain was created on 21st of September, 2011. So the Domain age should be:
1 year, 3 Months, 2 days.
or
1 year, 92 days
or
1 year, 3 months
I use Piwik 1.9.2
Keywords: domain age
Now (22.12.2012 - 22:54) I get:
Domain age: 1 hours 40 min
Thanks for the report. That issue was already fixed in another ticket. With latest beta your domain is reported with 1 year and 93 days.