All webcomics have problem with comic time being slower than real time, some examples available on tvtropes. Obviously, whole EGS which started in 2002 and barely covering more than year of comic time (see the timeline) is good example, but the ration is not linear ... let's list the more interesting examples.
Note that it can actually cause problems, or at least make the Technology progress in EGS look weird ...
Most comic time per real time Edit
First the inverse: most comic time passing in smallest amount of real time is obviously the half year long timeskip done on EGS Main Story Comic for 2013-02-01.
Most real time for comic time Edit
The obvious winner in terms of ratio of real time to comic time is in There be Whales Here 3: The two-thirds of second Tedd was falling took whole week since EGS Main Story Comic for 2013-01-22 to EGS Main Story Comic for 2013-01-28 (5 pages). That is ratio 907200:1.
Notable long days Edit
Grace's Birthday Party runs from EGS Main Story Comic for 2005-05-23 ("Let’s Get This Matter Out Of The Way, Shall We?") to EGS Main Story Comic for 2006-09-29 ("The End"), 151 pages over 495 days to cover again maybe eight hours.
In Squirrel Prophet parts 2 and 3 the characters come into shop on EGS Main Story Comic for 2014-04-15 and leave few hours later at EGS Main Story Comic for 2014-12-30 just to end the day probably not whole hour later on EGS Main Story Comic for 2015-02-11.
Playing With Dolls started EGS:NP Comic for 2014-08-01 and ended at EGS:NP Comic for 2015-01-19 again covering just few hours and being the SAME day as the Date At The Mall (also, Question Mark happened the same day).
Longer periods Edit
Title "Last October (Holy crap, this predates Goo!)" on EGS Main Story Comic for 2010-08-18 refers to something happening BEFORE start of comics, which is mentioned in that title, as well as in commentary.
Title "June 7th continues. Again. It will never end." on EGS Main Story Comic for 2012-06-04.