There is an article on JTW in Great Falls Tribune (if you are collecting stories on Census 2000 coverage):

 

http://www.greatfallstribune.com/communities/census2000/20010822/900793.html

 

Other than me adding to the speculation that it may just be as easy to walk during winter months than to shovel snow, wait for the car to heat up or even wait for roadways to clear and drive in snow/sleet – people in those Northern States may have adopted to living closer to work – following excerpt is from the above article:

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Montanans' willingness to walk may reflect the short distances most have to travel to their jobs, even in a state of 147,000 square miles. About 9 percent live five minutes or less from work, more than twice the national average of almost 4 percent.

A third of Montanans travel fewer than 10 minutes to their jobs and 71 percent get to work in less than 20 minutes. Only three states had a higher percentage of commuters with such short trips.

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With his portrait of Pablo Picasso "looking" over his shoulder, artist Tom Gilleon puts a finishing touch on a painting at his home studio west of Cascade Tuesday. The Picasso portrait is for a Canadian client making a mosaic of 100 famous faces.