sex help

Has anyone ever gotten into a slump with sex? My husband and I have been married a little over a year now and we have sex regularly but seem to be in a bit of a rut right now and it's just not spontaneous anymore. Are schedules are kinda different and we're both busy and so tired at the end of the day that it seems like sex can be put to the back burner sometimes. Any advice on how to keep sex exciting?