I am curious what is offered in different places. For instance, traveling in Yellowstone I was surprised that they only accepted types 1 and 2 at most recycling receptacles. I figured a national park (especially one with a history of problems with its trash) would be on the leading edge, but then I suppose there aren't that many facilities to process material in NW Wyoming. The city of St. Louis does not allow type 6 though there is a re-purpose facility for polystyrene not too far away.
From wiki, here is a breakdown of the numbers:
1 signifies that the product is made out of polyethylene terephthalate (PET) (beverage bottles, cups, other packaging, etc.)
2 signifies high-density polyethylene (HDPE) (bottles, cups, milk jugs, etc.)
3 signifies polyvinyl chloride (PVC) (pipes, siding, flooring, etc.)
4 signifies low-density polyethylene (LDPE) (plastic bags, six-pack rings, tubing, etc.)
5 signifies polypropylene (PP) (auto parts, industrial fibres, food containers, etc.)
6 signifies polystyrene (PS) (plastic utensils, Styrofoam, cafeteria trays, etc.)
7 signifies other plastics, such as acrylic, nylon, polycarbonate and polylactic acid (PLA)
Note: I don't know how to change this from a radio button poll to mark all that apply so all I did was set the max votes per user to 7 (since the first 7 options are mutually exclusive with the 8th).
Edit: It looks like the select-all works but the wrong denominator is used for the response rate. The real percentage should be responses for each option divided by the number who have responded (not the total number of responses across all categories). Ah well