Interesting thread for me right now as I approach the number.... Sort of: I'll show you mine if you show me yours :)
The basic answers for us are: Any week/month now to hit $1M NW at age 44 for me, 38 for wife. (We've been a couple for 10 years, married for 8 with one son, still in the expensive preschool years).
My story is not too straight of a line; spending most of my 20's doing 'interesting things' that didn't pay much (or that even required loans :), though I've always been a saver at heart. What interesting things? Oh, full time alpine ski racing coach in S. Lake Tahoe, on the organizing committee/staff for the Atlanta Olympics, going back to school full time for an MBA... Once I did finally settle into my now career portion of life (just as I hit age 28), I started out at $48K. Eventually jumping that number over the six figure barrier a few years ago, but also including 2 layoffs from being downsized out of both the tech bubble and real estate bubble. Wife never made all that much (~$28-35K) until a few years ago and now her career has taken off in many ways, including financially, as she has now roughly tripled her income from when we met.
Also a 'lost decade' in the stock market just as I started my investing for FI. I bought plenty of shares over the years that have finally blossomed during the recent upturn in the markets. Plus a now paid off condo where I/we lived for 11 years, that is now a rental property. And also some small equity in our 2.5 year old house (with cheap rates and RE prices only looking like upward growth, I only put 5% down on the place and kept my taxable accounts going strong).
In time:
1998, 28 yrs old, -$10K in NW ($15K in student loans)
2000, 30 yrs old, $35K NW (down to $5K in student loans)
2002, 32 yrs old, $85K NW (had bought the condo, no more student loans)
2004, 34 yrs old, $175K NW
2007, 37 yrs old, $315K NW (Somewhere in here I married into about -$15K of NW from my wife, plus we paid for her masters degree)
2010, 40 Yrs old, $485K NW (Expensive NICU stay for Jr birth in here, condo paid off about here as well)
2012, 42 Yrs old, $725K NW (house purchase in late '11)
2014 (as of Mar 31), 44 yrs old, $970K NW
So it turns out that you can 'waste' much of your 20's (FI wise), marry into negative NW, invest during a horrible 10 year stretch of the markets, get laid off twice, have a very expensive medical bill and deal with other of life's bobbles and still hit ~$1M by mid-forties if you work really hard at your career (aka improve income opportunities) and save, save, save the whole time...
Rough numbers today:
$550K Retirement Accounts
$190K Taxable Accounts
$230K total RE Equity
I don't count cars or other 'stuff' as financial assets for NW, otherwise I could probably claim $1M today.
I'll probably work a good 7 or so more years to pay off the house and build up plenty of cushion. I've seen some of life's detours already and want to feel secure. Then do PT work to stay busy, but not too busy.