At various times it would be used by all those female members who are breastfeeding children. They wouldn't use it, for example, for every division. Sometimes they'll appear for a vote, but at other times they'll give their proxy vote to their whip.
I should emphasize two things about the proxy vote. The member does need to be in Canberra and they do need to be in Parliament House to be able to exercise it. It can't be done remotely. You can't be back in your electorate exercising your proxy vote. Similarly, you can't be at your residence here in Canberra and exercising your proxy vote; you need to be in Parliament House.
It is used very regularly by the women with breastfeeding children.