Thread: за последние полгода

That is not only for year, but for any noun actually.

"За последние полмесяца на нашем сайте было в среднем полтора посетителя в день, и писалось по полкомментария в неделю."

Yes, yes, it was clear. It was me that has expressed badly.
As for neuter I think if it isn't by the same uses as in other constructions with numbers, omitting число. I don't remember exactly, but it was something like:
There were 35 persons. Там было (число) 35 человек. Спасибо.