Repeat quarterly variables two times to generate a monthly variable.
Examples
tsq <- ts(1:20, start = c(1990, 1), frequency = 4)
tsqm(tsq)
#> Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
#> 1990 1 1 1 2 2 2 3 3 3 4 4 4
#> 1991 5 5 5 6 6 6 7 7 7 8 8 8
#> 1992 9 9 9 10 10 10 11 11 11 12 12 12
#> 1993 13 13 13 14 14 14 15 15 15 16 16 16
#> 1994 17 17 17 18 18 18 19 19 19 20 20 20