R(t) was calculated using the EpiEstim package, developed by Cori et al. (2013; DOI: 10.1093/aje/kwt133), in the R software environment. Case recorded date was used as the time anchor, except for the Ontario R(t) value. Estimate of R(t) uses a 7-day window, and a Generation Time consistent with current literature (mean 3.5, SD 3.3). I use case data sourced from the Government of Ontario (2021, ontario.ca). Weekly cases per capita uses population data sourced JP Soucy and Isha Berry (2021, https://github.com/ccodwg/Covid19Canada). Percent positivity is supplied on a 7-day average by the Government of Ontario (2021, https://data.ontario.ca/dataset/ontario-covid-19-testing-metrics-by-public-health-unit-phu). I use case data sourced from the Government of Ontario (2021, ontario.ca). The 50% exposure statistic is explain in my section on RISK. The date to achieve is based off the current case count and the current R(t) value.