Gnuplot question

Hi!

Let's say I have these two columns in file.txt

0 1
1 5
2 10
3 15
4 20
5 25

in gnuplot, i would plot using

plot 'file.txt' u 1:2

If I wanted to add a label to the y-axis I would use

set label "Ef" at 0.0,7.0

However, I want the label Ef to be on the otherside of the y-axis. Not on the graphing area. How may I do this? Thanks