Create a column which is an average of other columns

[Martiox10]

Hello,
I would try to create a new variable, which is the average of some of the other variables. I am working with countries and their GDPs (per month) and it asked me to make the average of them. Would someone here be able to help me in this ?
Thanks

[williaml]

Hi, what does your dataset look like? Can you provide a reproducible example? It would make it much easier to help.

FAQ: How to do a minimal reproducible example ( reprex ) for beginners

A minimal reproducible example consists of the following items: A minimal dataset, necessary to reproduce the issue The minimal runnable code necessary to reproduce the issue, which can be run on the given dataset, and including the necessary information on the used packages. Let's quickly go over each one of these with examples: Minimal Dataset (Sample Data) You need to provide a data frame that is small enough to be (reasonably) pasted on a post, but big enough to reproduce your issue. Let's say, as an example, that you are working with the iris data frame head(iris) #> Sepal.Length Sepal.Width Petal.Length Petal.Width Species #> 1 5.1 3.5 1.4 0.…

[fcas80]

I created some sample data:

df <- data.frame(cbind(
         January = c(100, 200, 300),
         February = c(110, 205, 307),
         March = c(117, 211, 315)))
rownames(df) = c("Albania", "Bahamas", "Chile")
df$average <- round(rowMeans(df),1)

df

        January February March average
Albania     100      110   117   109.0
Bahamas     200      205   211   205.3
Chile       300      307   315   307.3

[nirgrahamuk]

Hello,
I'm sure you shared this image with the best intentions, but perhaps you didnt realise what it implies.
If someone wished to use example data to test code against, they would type it out from your screenshot...

This is very unlikely to happen, and so it reduces the likelihood you will receive the help you desire.
Therefore please see this guide on how to reprex data. Key to this is use of either datapasta, or dput() to share your data as code

FAQ: How to do a minimal reproducible example ( reprex ) for beginners

A minimal reproducible example consists of the following items: A minimal dataset, necessary to reproduce the issue The minimal runnable code necessary to reproduce the issue, which can be run on the given dataset, and including the necessary information on the used packages. Let's quickly go over each one of these with examples: Minimal Dataset (Sample Data) You need to provide a data frame that is small enough to be (reasonably) pasted on a post, but big enough to reproduce your issue. Let's say, as an example, that you are working with the iris data frame head(iris) #> Sepal.Length Sepal.Width Petal.Length Petal.Width Species #> 1 5.1 3.5 1.4 0.…