"averages" used on clicky

I see averages being used in many locations on clicky.

On the visitors graph I can view it for "Same day of week average". How many weeks are used to calculate that average?

Also, there are red and green percentages that signify how much traffic is up or down. If I most over them they will say something like... "~1,744 on average at 9:44am". Is that a "same day of week average?"... and how many weeks is that calculation based upon?

I like having these options, but they will mean a lot more if I know how they are calculated.

Thank you.

These averages are based on the last 4 weeks.

Thank you!