I haven't seen this sort of data before and it's an interesting way of looking at job access, transit connectivity, and overall built form:
The above is a table from New Geography (using data from the University of Minnesota). And what it shows is how many more jobs, across the US, can be accessed within a 30-minute commute by car versus by transit. For example, what this data tells us is that, on average across the US, there are about 56x more jobs that can be quickly accessed by car versus by transit.
But there is also huge variation across the 50 largest cities in the US. On the top end is Detroit, where there about 130x more jobs that can be accessed by car (again within 30 minutes). This isn't at all surprising. Also not surprising is the fact that New York is on the lowest end with only 5.6x as many car-versus-transit jobs. This is one of the reasons why I spoke yesterday about NYC being such an ideal candidate for something like NYC 25x25 .
What a lower number tells us is that the city is far less reliant on personal vehicles and almost certainly has a higher urban density. That's why you see cities like New York, San Francisco, Boston, and Chicago near the top of this list. And in my opinion, this is where you want to be. The goal should be to minimize this multiple.
I haven't seen a dataset like this before, but I'm now curious to see how it varies globally. It feels like something that more of us should be monitoring. Because we know that there are strong links between jobs access and the overall economic performance of a city.