Ok to add to the days driven per year stats, here is a "significant patches per year" stat*:
09 | 1?
08 | 1
07 | 2
06 | 2
05 | 3
04 | 3
*this is subjective from a quick search, definitely not conclusive!
What I considered significant patches:
12/2003 0.3E S1
03/2004 0.3F S1 - patch that was current when I found LFS early April 04
04/2004 0.3G S1
10/2004 0.5K Pre official S2
04/2005 0.5L
06/2005 0.5P First S2 with full content
04/2006 0.5T
12/2006 0.5V
06/2007 0.5X
12/2007 0.5Y
07/2008 0.5Z
11/2009 0.5Z28 questionable as to how significant, really the next patch release with significant new content is the next one in the line.
So really content peaked in mid 05 with some solid improvements in 06 which then has tapped since, so while LFS online numbers stay relatively constant it can be seen that long term player usage does correlate somewhat with significant patch releases*. No surprise to most of us though I should imagine