Loading packages…

library(dplyr)
library(ggplot2)
library(extrafont)

First, we download the TTF files, defining the Decima WE font, from https://www.download-free-fonts.com, and we put them in the directory ~/.local/share/fonts/. Then, we import them into our R session:

font_import(paths = "~/.local/share/fonts/",prompt = F)

If you use package ggplot2, you can use the font with command

+ theme(text = element_text(family = "Decima WE")).

Here an example:

p <- ggplot(airquality %>% mutate(Temp=cut(Temp,breaks = c((5:10)*10))),
            aes(x=Wind,y=Ozone)) + geom_point() +
  facet_grid(Temp~Month, labeller = label_both) +
  theme_bw()+
  theme(
    text = element_text(family = "Decima WE", color = "grey20"),
    strip.background = element_blank(),
    strip.text = element_text(hjust = 0),
    panel.grid.major = element_line(colour="grey50",size=0.35),
    panel.grid.minor = element_blank(),
    plot.margin=unit(c(0,1,0,1),"cm"),
    legend.position="top",
    plot.caption=element_text(hjust=1,size=9,colour="grey30"),
    plot.subtitle=element_text(face="italic",size=12,colour="grey40"),
    plot.title=element_text(size=18,face="bold")) +
  labs(title="\nAn example",
       subtitle="using font Decima WE",
       caption="Notes: probably compliant with the new logo font ARPA-FVG\n",
       x=expression("wind"~(m/s)),
       y=expression("ozone"~(mu*g/m^3)))
  
  p