What is the best web site to find out how many shares are currently Shorted (and the Short Interest ratio) on a particular ETF?
Don’t think it’s monitored. Problem with an ETF is the outstanding shares can change as they can be redeemed or created so theirs no hard value.
I doubt many ETF's are directly shorted, any trader wishing to do so would do so via a BEAR ETF or Inverse ETF, same thing. On USA Market I couldn't find freely available short list, like there is on ASX.... https://www.marketindex.com.au/short-selling
The link I provided above does show short interest or number of shorted shares for ETFs. May not be 100% accurate, especially due to ETF share creation and destruction, but it shows whatever data may be available.
Ya, but, gotta admit, QQQ is ok, it's a reasonably safe bet for a trader. As for many others, ETF's appear to give substandard results. An example, I follow via data hundreds of stocks and their sectors, it's not uncommon for me to see a large number of stock in one sector rising on a partucular day while the ETF of that sector falls and vice versa on a day by day basis.