Editing Pareto principle (section)

=== Health and social outcomes ===
In 2009, the [[Agency for Healthcare Research and Quality]] said 20% of patients incurred 80% of healthcare expenses due to chronic conditions.<ref>{{cite web|url=http://www.projo.com/opinion/contributors/content/CT_weinberg27_07-27-09_HQF0P1E_v15.3f89889.html|title=Myrl Weinberg: In health-care reform, the 20-80 solution|last1=Weinberg|first1=Myrl| website=The Providence Journal|date=July 27, 2009|archive-url=https://web.archive.org/web/20090802002952/http://www.projo.com/opinion/contributors/content/CT_weinberg27_07-27-09_HQF0P1E_v15.3f89889.html|archive-date=2009-08-02}}</ref> A 2021 analysis showed unequal distribution of healthcare costs, with older patients and those with poorer health incurring more costs.<ref>{{cite web |last1=Sawyer |last2=Claxton |first1=Bradley |first2=Gary |title=How do health expenditures vary across the population? |url=https://www.healthsystemtracker.org/chart-collection/health-expenditures-vary-across-population/#item-discussion-of-health-spending-often-focus-on-averages-but-a-small-share-of-the-population-incurs-most-of-the-cost_2016 |website=Peterson-Kaiser Health System Tracker |publisher=Peterson Center on Healthcare and the Kaiser Family Foundation |access-date=13 March 2019}}</ref>
The 80/20 rule has been proposed as a rule of thumb for the infection distribution in [[superspreading event]]s.<ref>{{cite journal|last1=Galvani|first1=Alison P.|last2=May|first2=Robert M.|year=2005|title=Epidemiology: Dimensions of superspreading|journal=Nature|volume=438|issue=7066|pages=293–295|doi=10.1038/438293a|pmid=16292292|bibcode=2005Natur.438..293G|pmc=7095140}}</ref><ref name="Lloyd-Smith JO 2005" /> However, the degree of infectiousness has been found to be distributed continuously in the population.<ref name="Lloyd-Smith JO 2005">{{cite journal|last1=Lloyd-Smith|first1=JO|last2=Schreiber|first2=SJ|last3=Kopp|first3=PE|last4=Getz|first4=WM|year=2005|title=Superspreading and the effect of individual variation on disease emergence|journal=Nature|volume=438|issue=7066|pages=355–359|doi=10.1038/nature04153|pmid=16292310|bibcode=2005Natur.438..355L|pmc=7094981}}</ref> In [[epidemic]]s with super-spreading, the majority of individuals infect relatively few [[contact tracing|secondary contacts]].