New regression models were constructed to better understand the performance of different home composting groups, to test the assumption that diversion factors are not seasonal, and to provide a better fit to the data, particular for garden waste. Diversion factors were produced for three groups of home composting households:
- Non-WRAP home composters – those that home composted without a WRAP bin;
- WRAP Enhanced – those households that composted prior to receiving their WRAP bin
- WRAP New Recruits - those household that did not home compost prior to receiving their WRAP bin.
Analysis of waste composition and questionnaire data collected in 2004 from nine local authorities produced the following diversion factors (negative values indicate diversion and bold indicates significantly different from zero):