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DF <- read.csv("~/R/Play/Dummy.csv", sep = " ")
library(tidyr)
library(ggplot2)
DFlng <- pivot_longer(DF, cols = Sep:Aug)
head(DFlng)
#> # A tibble: 6 x 4
#> MY TOTAL name value
#> <int> <int> <chr> <dbl>
#> 1 2009 100 Sep 7.43
#> 2 2009 100 Oct 13.7
#> 3 2009 100 Nov 21.6
#> 4 2009 100 Dec 29.9
#> 5 2009 100 Jan 38.5
#> 6 2009 100 Feb 45.4
DFlng$name <- factor(DFlng$name, levels = c(month.abb[9:12], month.abb[1:8]))
DFlng$MY <- factor(DFlng$MY)
ggplot(DFlng, aes(x = name, y = value, group = MY, color = MY)) + geom_line()

Created on 2021-06-03 by the reprex package (v0.3.0)