The problem with the data it is estimates based on known information, such as truck movement numbers or landfill airspace surveys. The waste industry doesn't measure tonnages, unless the receiving sites have weighbridges or equipment with load cell tranducers. Most sites receiving waste or recycling materials have neither, so other known data is used to extrapolate estimated tonnages.
Also, the waste industry is disjoint from the packaging and manufacturing industry, so it is very difficult to know real recycling rates. Again these are estimated based on best available information, which is extrapolated to provide recovery and recycling rates. If the same methods are used from year to year, then trends can be determined and tge trends can be seen as more reliable indication of the situation than raw data.
Notwithstanding this, the data really shown the magnitude of what is occurring, rather than exactly what is occurring.
Such is enough to provide information for policy guidance and development, however, could also be manipulated to drive a particular agenda to push for a particular policy outcome.
This is why it is best to read the State and Commonwealth reports, as well as local government reports if available to determine if similar intrerpretation are given. If interpretations are wide apart, then the presented data and conclusions becomes more questionable.