Here's the timeline I prefer. There are inconsistencies ... but this lines up the best, and makes the most sense to me ...
-- Bruce returns from Princeton when he is 21 (in 1996), and disappears for seven years after Joe Chill is killed (gone between 1996 and 2003);
-- He returns to Gotham when he is 28, in 2003, and becomes Batman for the first time.
-- The Ras al'Ghul attack happens on his 30th birthday in 2005. The first Joker robberies happen in the same year (calling card at the end of BB);
-- Between 2005 and 2008, Joker gains notoriety and Batman works his way up the mob ladder (wearing the original BB suit), and Rachel Dawes does not age well ... she looks awful come 2008.
-- Events of TDK happen in 2008 ... new suit, Joker killings, death of Harvey Dent. Last appearance of Batman, age 33.
-- Batman in retirement from 2008-2016.
-- Events of TDKR occur in 2016 -- Bruce is now 41.
That would leave Bruce as Batman from age 28 to 33 (2003-2008), and again at age 41 (2016). Those years make sense to me, those ages makes sense ... and the five-year timeline before retirement is more satisfying than the 18-months or whatever people are using. Also leaves a reasonable off-screen gap for an active Batman between BB and TDK.
There are some inconsistencies. The new book cites Harvey Dent's injuries as occurring in 2004. There is something about TDKR referencing 2014. But, the above seems to line up the best. Here is a more detailed timeline I got off of another board ...
Maybe Batman Begins from his first night out to defeating Ra's does actually take place over a couple years, as Zach suggested:
--and it is from:
2003 - 2005
Things that suddenly fit if we accept this, and assume that TDK takes place in 2008:
2003 - Bruce Wayne returns to Gotham City, has his first night out, begins prowling as the Batman.
2003 - Jimmy is a two year-old infant when Batman visits Gordon at home.
2005 - Batman defeats Ra's Al Ghul on the train. Remember this is on the SAME NIGHT that he has his 30th birthday party.
2005 - 2008 - Offscreen, Batman wages war on crime, working his way up to the big fish of the mob. Assuming this is true conveniently explains several things:
- (1) Like SnakeDoc suggests, it is not until a year before TDK that he is finally having an impact that is really hurting them and making them take notice.
- (2) All during this time, while Batman is building his reputation, Joker commits random crimes and builds up his own legend among criminals. This is where we get the "So why do they call him the Joker?" "I heard he wears makeup..to scare people...y'know, war paint" lines. It makes sense that it takes a while to build up that kind of rumormill/reputation. It also explains the "Two-bit wack job, cheap purple suit" line from Maroni and the "Him again" line from Batman. Joker wasn't wearing the purple suit during the bank robbery, so Maroni must have seen/heard of him before. Like Batman, dispite his crimes, he views him as just a minor nuisance to be dealth with later.
- (3) Guestimating this three-year gap between the films also neatly explains the line in The Dark Knight Manual that he was wearing the Original Suit for 5 years---he was---from 2003 to 2008.
- (4) Finally, this 3 year gap ages little Jimmy almost perfectly. If he is two years-old in 2003, then he is seven in 2008. It doesn't take much stretching in either direction to make him an 8 year-old, or to even just assume he is supposed to be seven in that film.
The Dark Knight Rises is eight years later.
2016 Now I know the Gotham Civil War poster contradicts this, with the date of the exhibit ending in 2014. But this is the only really hard-set date we know of (as of now anyway), and it's not really clear if it even appears noticeably on-screen or if a hard-set date of 2014 appears in the final film on screen, so I'm willing to overlook it. Also, I realize this is just an excuse, but that poster could be an "old" ad that was never taken down, or pasted over with something else newer that is peeling off. It certainly doesn't look like it's supposed to be in new condition. Just sayin'.
Working backward from the above dates, we can make the milestones in Bruce's life fit too.
2003 - Bruce Wayne returns to Gotham. Based on the above that he turns 30 in 2005, he turns 28 in 2003. Since we know he was away for seven years, he dropped out of Princeton at 21 (or 20, depending on his birthday) as an undergrad in his senior year, just shy of graduation.
Working farther back and using the casefile of the Wayne murders in The Dark Knight Manual
November 8, 1983 - The Waynes are gunned down. Bruce is 10 or 11 years old (again, depending on his birthday)
1972 or 1973 - Bruce Wayne is born.
So,to answer the question, that would leave Bruce Wayne fighting crime between 2003 and 2008 , and then again in 2016 ... about six-years total before the end of TDKR.
Whether you want to think he eventually comes back after TDKR is up to you.