creating new variable from variable in frame

I am a newbie to R...
I have a data frame with a column "accnt". How do I assign the new variable "defer" to "Y" if accnt is between 5 and 9 inclusive, otherwise assign "N"?
Thanks!

Here is a simple method:

DF$defer <- ifelse(DF$accnt >= 5 & DF$accnt <= 9, "Y", "N")