Transposing in LilyPond

Now I always suspected that there is an easy way of transposing music. But with LilyPond, it is just ridiculously easy. To transpose from pitch x to pitch y one simply has to insert \transpose x y in front of the expression to be transposed. For instance, to transpose The Pink Panther Theme from E minor to A minor all I had to do was to add \transpose e a, just after \new Staff line. (If I type \transpose e a it works too but the resulting score is one octave higher than I want.) Voilà!