Portfolio Manager tracks 28 types of waste and materials, plus "Other" for anything that doesn't fit into one of the other 28 categories, for a total of 29 possible.
The Waste Meter types are a combination of one of the 4 Waste Management Methods (Disposed, Recycled, Composted, Donated/Reused) and one of the 29 Waste Material Types. For example, Disposed - Trash or Donated -Furniture.
There are 72 total Waste Meter Types (not 4 * 29) because some of the Waste Material Types cannot be composted (batteries), recycled (food scraps), or donated (mixed paper). All of the 29 Waste Material Types can be Disposed.
*These types of Waste don't have a standard volume-to-weight conversion factor. You will need to enter a weight (rather than a volume) for these waste types. See this FAQ for more information.