This matrix shows the played time in minutes per day of the week over the
last 28 days. The minutes are counted per player to represent a measure for playing activity for every given interval.
Only games that were publically announced are counted. We don't notice other games, thus we
can't count them.
These times are in UTC aka GMT. E.g. Germany is UTC+1/GMT+1
and therefore, any given time in this table has to increased by 1 hour to match Germany's time.