rdatezooyearmonth

Subtract months from time in format year-month

I want to subtract months from given date in year and month format. 

global_date = "2017-01"

I am converting it with the zoo library as follows:

as.yearmon(global_date) - 0.1

but it gives me Nov 2016, I want it as '201612'

How can I do it in R?

Solution

  • As we want to subtract one month, we should subtract 1/12 which is 0.083 and not 0.1

    library(zoo)
as.yearmon(global_date) - (1/12)
#[1] "Dec 2016"

    If we need output in the mentioned format

    format(as.yearmon(global_date) - (1/12), "%Y%m")
#[1] "201612"