Google analytics : Links interessantes
Variáveis (customizáveis): http://thinkvitamin.com/business/analytics/google-analytics-tweaks/
LeituraConsolidada.objects.filter(data_leitura__year='2011').extra(select = {'mes':'extract(month from data_leitura)'}).values('mes').annotate(Avg('ozonio'), Avg('dioxido_enxofre')) #Saida [{'ozonio__avg': 24.965, 'dioxido_enxofre__avg': -0.42499999999999999, 'mes': 1.0}, {'ozonio__avg': 43.613333333333337, 'dioxido_enxofre__avg': -0.28000000000000003, 'mes': 2.0}] LeituraConsolidada.objects.filter(data_leitura__year='2011').extra(select = {'mes':'extract(month from data_leitura)'}).values('mes').annotate(Avg('ozonio'), Avg('dioxido_enxofre'))