A further use for a classification identified in consultations is to audit the spread of public health activity, expenditure or investment, across the business cycle -from health problem identification and assessment to program or intervention planning and design, through to implementation and evaluation of results. This suggestion arose out of concerns that public health activity is too heavily weighted towards implementation, and that there is insufficient evaluation of interventions, and learning from and progressing beyond pilots. A related use is to examine the spread of all public health investments, for example, by Australian, state, territory, and local governments, NGOs and other investors; the links to employment and education; and public health investment by, and outcomes in, other sectors such as transport and housing.