Bagaimana cara mengubah lebar garis di ggplot?

Datalink: data yang digunakan Kode saya: ccfsisims <- read.csv(file = "F:/Purdue University/RA_Position/PhD_ResearchandDissert/PhD_Draft/GTAP-CGE/GTAP_NewAggDatabase/NewFiles/GTAP_ConsIndex.csv", header=TRUE, sep=",", na.string="NA", dec=".", strip.white=TRUE) ccfsirsts <-...