Unfortunately, knowing what is normal waste generation per capita isn't going to help you much when it comes to being sustainable.
To put it simply, the current reality is that it's normal to be unsustainable. That needs to change.
There are two things most people can do to heavily reduce waste without too much effort, depending on their situation:
- Compost your compostables
- Recycle your recyclables
These actions not only reduce waste, but also make more efficient use of the land used for landfill (which is expensive, when done properly), as well as reducing smell and leachate problems.
Unfortunately, it's also a reality that most recycling isn't carbon neutral. In New Zealand, our plastic is picked up by diesel trucks, and with various intermediate steps, is later shipped to China where it's recycled. Glass is ground up and used as road aggregate, which may even be worse than just piling it up somewhere (we could at least use it for glass later that way).
I'm in a household of 3, and we tend to fill a rubbish bag about every 2 weeks. We go one step further than the above, and bury our meat scraps (which are not compostable in your average composting system). Things that tend to fill it up are polystyrene foam, used tissues, and plastic packaging. Reducing purchases of products containing those things will be our next step.
Overall, my philosophy is that it's more important to be a positive example to others (to change what's normal) than it is to become an extremist myself. If I lived in a monastery somewhere living off the land, I might be 100% sustainable, but I wouldn't be mixing with others to set a visible example. That's why I'm on an unsustainable computer right now writing this post instead of using the time walking to a special store that will sell me some food without packaging.