More efficient way to create frequency column based on different groupings

Question

I have code below that calculates a frequency for each column element (respective to it's own column) and adds all five frequencies together in a column. The code works but is very slow and the majority of the processing time is spent on this process. Any ideas to accomplish the same goal but more efficiently?

Create_Freq <- function(Word_List) {
library(dplyr)
Word_List$AvgFreq <- (Word_List%>% add_count(FirstLet))[,"n"] +
                      (Word_List%>% add_count(SecLet))[,"n"] +
                      (Word_List%>% add_count(ThirdtLet))[,"n"] +
                      (Word_List%>% add_count(FourLet))[,"n"] +
                      (Word_List%>% add_count(FifthLet))[,"n"]
return(Word_List)
}
```