Event: EnterFrame in a clock example?

programming flash
1

Hi!
I´m just start with AS3 and I saw in an example how to made a simple clock, but it is using enterFrame event, if my movie is working at 30fps, is a good practice use enterFrame for a second counter?
Is there any other better function or better practice where I does not need to check 30 times in every second?

Thanks!