This package provides functionality to convert between Dates and Morbidity and Mortality Weekly Report (MMWR) weeks (day, week, and year).

The first day of any MMWR week is Sunday. MMWR week numbering is sequential beginning with 1 and incrementing with each week to a maximum of 52 or 53. MMWR week #1 of an MMWR year is the first week of the year that has at least four days in the calendar year. This package provides functionality to convert Dates to MMWR day, week, and year and the reverse.

library(MMWRweek)
MMWRweek('2015-11-24')
#>   MMWRyear MMWRweek MMWRday
#> 1     2015       47       3