I guess we should get terminology out to the way first. This EPA report is on municipal solid waste (MSW), which is defined for this study as:
These materials include items such as packaging, foodWaste generation is all of the waste that ends up in a trash can, recycling bin, dumpster, and/or left at the curb. The first figure we'll look at is the trends in waste generation over the last 50 years.
scraps, grass clippings, sofas, computers, tires, and refrigerators. MSW does not include industrial, hazardous, or construction waste.
Next we'll take a look at the composition of MSW in the U.S.
I like this chart because it's interesting to try to explain why we the variation that we do. Auto batteries are easy since a lot people get them changed at shops who typically are required by law to recycle them. They are also considered hazardous waste and contain valuable materials. Office paper is high because so many offices and such have recycling programs and people are generally good about separating it out of the trash. I would think steel cans have such a high rate because they are valuable and they are readily removed from waste streams with a magnet. Aluminum is more valuable, but eddy current separators are going to be more costly than simple magnets. Yard trimmings have such high rates due mostly to yard waste landfill bans that are in place in about half the states. I want to do a post in the future on the benefits of recycling various materials.
Finally, I want to look at how waste is treated in the U.S. We see that over half our waste ends up in landfills. About 25% goes to what I would call traditional recycling, which consists of turning things like metals, paper, plastics, and glass into new materials. Another 12% (the State of Garbage reports calls it 18%) is combusted for either steam or electricity generation, and finally another 9% is aerobically composted. If I had to guess based on the trends discussed earlier and some intuition, I would say the composting is probably going to increase, recycling will increase more slowly than composting, and combustion will stay about the same as landfills decrease.