ggplot increase size of points

February 11, 2023

I have a scatter plot that includes different colours for different types of sales as well as different sizes based on the amount of the sales. However, the points are currently very small and I want to increase them. Is there a way to increase all points in the chart? I tried adding scale_size_area(scale = 5) but the points keep the same size.

My code is this

ggplot(abc, aes(x = year, y = amount, color = type, size=amount)) +
  geom_point()+
  guides(color = guide_legend(override.aes = list(size=5)))+
  labs(y= "Amount sold", 
       x = "Year",
       title="",
       fill="Type") +
  scale_size_continuous(name="Size of sales") +
  theme_classic()

and my dataset looks as follows:

structure(list(year = c(2009L, 2011L, 2012L, 2012L, 2012L, 2013L, 
2013L, 2014L, 2014L, 2014L, 2014L, 2014L, 2015L, 2015L, 2015L, 
2016L, 2016L, 2016L, 2016L, 2016L, 2016L, 2016L, 2017L, 2017L, 
2017L, 2017L), country = c("Spain", "France", "France", "Italy", 
"Spain", "France", "Spain", "Italy", "France", "Italy", "Italy", 
"Italy", "Spain", "Italy", "Italy", "Spain", "Portugal", "Spain", 
"France", "Spain", "Spain", "Italy", "Portugal", "Italy", "France", 
"Spain"), type = c("Food", "Food", "Food", "Food", "Food", "Food", 
"Food", "Food", "Food", "Metal", "Food", "Food", "Food", "Food", 
"Food", "Cars", "Food", "Cars", "Cars", "Food", "Metal", "Cars", 
"Metal", "Food", "Food", "Cars"), amount = c(0.164692692, 1.47320717, 
2.87002149, 0.040626329, 0.110603352, 0.006904824, 0.123085039, 
0.024957478, 4.1241304, 0.499484718, 0.060575151, 0.171695527, 
2.106156361, 0.915858692, 0.056212947, 1.65235, 1.167061203, 
0.046784638, 0.490756212, 0.328276233, 0.189537764, 0.954012362, 
0.470978739, 0.078503892, 0.253975843, 0.2738115)), class = "data.frame", row.names = c(NA, 
-26L))

Thank you very much!

>Solution :

Add range= to your scale_size_continuous. An exaggerated example:

ggplot(abc, aes(x = year, y = amount, color = type, size=amount)) +
  geom_point()+
  guides(color = guide_legend(override.aes = list(size=5)))+
  labs(y= "Amount sold", 
       x = "Year",
       title="",
       fill="Type") +
  scale_size_continuous(name="Size of sales", range=c(2, 20)) +
  theme_classic()