If you are looking at a 40 year US home, it may only have R15 or R20. If you are looking at a new normal home in the midwest, you are looking at an R40 or so. If you custom build you can pay the extra few hundred bucks and get R60 or more..
I don't know the current percentage, but passive houses (https://en.wikipedia.org/wiki/Passive_house) are getting more and more in this area.
Not beeing in the construction business I can't give you any details how the way we insulate our houses compares to your information. Most of the houses here are built with concrete and bricks, so they're insulated differently (styrofoam, as much as I know).
Chicago average temperature: http://www.holiday-weather.com/chicago/averages/
Sydney average temperature: http://www.holiday-weather.com/sydney/averages/
In Sydney, your primary concern is heat. In Chicago, your primary concern is cold. They have different strategies to combat. I.e. good blinds could cut your cooling bill 50% in Sydney. Good blinds will not make a dent in your Chicago bill..
Innsbruck average temperature: http://www.holiday-weather.com/innsbruck/averages/
That's pretty close to Chicago.