I find that hard to believe and what I've observed, with all the TOD around Metra stations that wasn't there in 1980. At stations like Palatine, Arlington Heights, I see tons of people getting off the trains in the evenings and they go fanning out all over walking home, not just heading for the parking deck.
Maybe the number of commuters has held constant, but there is definitely more housing in walking distance than there was.

It's deceptive, I think; many of those towns always had a stream of commuters fanning off the train in the evenings, even when it was all single-family houses. I looked up the numbers for Arlington Heights specifically a few years ago, and amazingly the ridership there is essentially flat over the past 30 years despite them densifying their downtown. If you look at that website, the clear trend is that the only stations with growing ridership are the ones who are expanding their parking lots.

You're correct about the housing growth, but that's limited to only certain towns, and usually the pro-growth towns are also building tons of additional downtown parking in multi-story garages. Lots of towns are not seeing that growth, though, even now - Mt Prospect still hasn't completed any TOD development in their downtown, although one is underway. Go to Barrington, or Riverside, or Hinsdale, and their downtowns are essentially frozen in amber except for minor development projects that are basically just beautification. It's not that there's no demand, its that these towns are still enthralled with the suburban model of development and hate the idea of big, new buildings in their quaint, little downtowns.

Lastly, I think it's a mistake to assume that housing in suburban downtowns will automatically get filled with Metra commuters. We live in a big metropolitan area, and for folks who want an walkable lifestyle and work in downtown Chicago, the default choice will usually be to live in the city itself. Many of those suburban apartments are probably occupied by seniors or middle-aged people who want still convenient access to amenities, shopping and dining, but don't necessarily work in downtown Chicago or have a reason to ride Metra every day.

^Exactly. Looks to me like the demographic trends are swamping the (modest) development trends. Those condos by the train station are full of people who don't ride the train any more, if they ever did. Lots of widows, some empty nesters, a few singles and young marrieds who drive to work in nearby towns. Meanwhile, all those subdivisions for miles around the station are also full of retirees who don't ride the train any more. Maybe twice a year to some downtown museum with the grandkids.

Metra station trends
 

The fellow behind the Star:Line blog and Twitter account made this rather impressive comparison tool (just using Google Sheets!) for looking at the performance of various Metra stations:

Pabst Blue Ribbon Station Report

Almost all stations, it seems, are seeing declining boardings.

Does anyone know where to find updates on the 75th Corridor Improvement Project? The official site and the CREATE site are always out of date and don't have much information.

Doesn't seem that surprising considering the demographic trends of many suburbs. I'm not sure what Illinois and many municipalities can do to stop the decline though.

Spread the word that Tennessee, Georgia, Florida, Texas, Colorado, Arizona, and the Carolinas all cause cancer.

How can we account for the work from home trends? If 25% of employees are working from home one day a week it would result in a sizable decrease in boarding. Working from home has been growing perk for 2 decades.

Wouldn’t declining Metra boardings have something to do with all of those apartments and condos being built around downtown?

I mean, in 1980 living in the city was just not even a consideration for the professional middle class. Now it’s viable and, for many, preferred.

So in 1980 NO middle class professionals lived in the city? Ok, got it.

The other side of the stick is the huge rush of corporations back to the loop from the suburbs. Of course not all those employees would move to the city with them - I would have thought Metra would see an uptick from more suburban works who have to make the trek into downtown where their jobs are now setting up shop.

Maybe it's the difference between the two.

Really. How do you explain Marina Towers (1968), Sandburg Village (1968), the emergence of Old Town as an alt hood, Lincoln Park, DePaul. All of these neighborhoods had 'urban pioneers' settling in what was then dicey low income hoods as early as the late 60's and through the 70's. The back to the city movement really started with Marina Towers and Sandburg which targeted young upwardly mobile professionals. Airline attendants and pilots, doctors and nurses, lawyers were primary residents of Sandburg Village. Rush street earned its reputation during this era.

The issue is how we explain declining Metra boardings in the past 30-40 years despite rising downtown job growth.

My answer is that it must have something to do with the exponential growth of the professional class in and around downtown in that same time period. Yes, such people lived in the city in 1980, but a hell of a lot more do today. Hence all of those apartment and condo buildings in every which direction. Those are people who mostly would've lived in the suburbs if it were 1980, but instead are living in and around downtown, and thus aren't Metra commuters.

That's just one hypothesis. Maybe it also has to do with sprawl, increased car commuting, etc?

^ Yeah, in the Chicago suburbs the idea of the "young professional-focused" apartment complex has largely died out, probably because everyone wants to be in the city. There are still a bunch of complexes from the 1970s and 80s, some of which retain a focus on young people (like Four Lakes in Lisle) but no developer in their right mind would build one now.

Even Mellody Farms in Vernon Hills, which has tried to be the coolest of the cool suburban developments (they even have one of those stupid "wings" murals), ended up targeting empty nesters for its apartment complex.

Do the Chicago suburbs have any of those faux-urban developments like Santana Row in San Jose or Kentlands in Gaithersburg MD?

You sort of get that with Streets of Woodfield

If I'm correct, I think Steely Dan is a huge fan of the place.

i'm there every other weekend.

LEGOLAND!!!!!

Our suburbs are littered with something like 100 historic downtowns along the rail lines (or sometimes off the rail lines). This satisfies suburbanites' desire for walkability, so unfortunately the parts of suburbia NOT along a rail line are auto-oriented to the max.

The Glen is really the only large-scale "New Urbanist" development, and even this is really just traditional suburbia with better landscaping and a somewhat walkable shopping area (the same as Kentlands, basically). Everything else is just a shopping mall where the covered mall has been replaced with a fake open-air street, and maybe a hotel or an apartment building is added for variety.

Streets of Woodfield is not even one of these, the site plan is exactly the same as a regular old suburban strip mall. It just has a more dining/entertainment focus and the buildings have a second story.

Other cities have done the "lifestyle center" thing much better, where they create a walkable grid of streets instead of just a single street surrounded by parking - Santana Row is good, Scottsdale Quarter in AZ, Easton in Columbus. DC is especially good at this, Kentlands notwithstanding - Reston Town Center, Rockville Town Center, etc

We've had a few attempts at a neotraditional new town center—Buffalo Grove Town Center, Burr Ridge Town Center, Wheaton Town Center, The Glen—but either the concept or the execution has always failed along the way. Burr Ridge and The Glen aren't laughably bad, but they're still entirely auto-oriented. A few suburbs have also done infill, primarily residential, neotraditional projects near their downtown rail stations: Libertyville School Street, a project near Skokie Oakton station, Park Ridge and LaGrange (both with Trader Joes as anchor).

We're pretty short on greenfield neotraditional subdivisions. Closest ones are some projects Bigelow Homes has done: Hometown Aurora and Hometown Oswego. There's also the "conservation community" Prairie Crossing near Libertyville. Coffee Creek in Chesterton, Ind., never amounted to very much.

In 2004, Zach Borders prepared a catalog of projects in the region that would be of interest to attendees of the Congress of the New Urbanism in Chicago. He cast his net pretty wide. (PM me if you'd be interested in a copy with minor damage.)

Chicago has something better - we have the real thing. Just take the Metra out to any of a number of communities - Riverside is great and not a long journey - walk around, and you'll experience the attempts to create such environments from whole cloth. Many of them are rather faded, including Riverside, but still a community.