See ```python >>> population[:'18-66', 2017:] age gender\time 2017 0-9 female 634 0-9 male 664 10-17 female 491 10-17 male 516 18-66 female 3583 18-66 male 3616 ``` in [selecting subset](https://larray.readthedocs.io/en/stable/tutorial/getting_started.html#Selecting-a-subset)