How Much Recycling Gets Recycled?

How much of the stuff we put in the recycling bin every week actually gets recycled? I got started thinking about this question one day when my girlfriend called me out on throwing away a plastic bottle instead of recycling it. I had just assumed that throwing away a bottle or a piece of paper once in a while doesn't make any significant difference since a lot of it probably ends up in a landfill, anyway. But, as is true of many of my self-serving beliefs, I really didn't know.

I tried to find an answer on the Internet, but found no leads. Then, the other day, I was listening to the Earth Day edition of the "Science Friday" radio program. Host, Ira Flatow was interviewing Daniel Imhoff, author of "Paper or Plastic: Searching for Solutions to an Overpackaged World". Here's what Imhoff said:

About 70% of paper and cardboard gets recycled. A lot is exported to countries where cardboard is "incredibly valuable".

About 50% of aluminum cans are recycled.

Only about 10% of plastic gets recycled.

Imhoff also had a lot of interesting points to make about overpackaging. Hopefully, I'll get time to read the book one of these days and report on it here.