Well, you can't "if" if there's no "how"
Exactly right. I went over the original question to see what he is asking, and the key points were institutional volume and block trades.
Well, institutional volume is very tricky. Its not like in addition to getting Time and Sales, the exchange tells you who bought and who sold. (ie. 1000 contracts bought by Goldman Sachs and sold to 1000 day traders in their basement doing 1 lots) LOL... how awesome would this info be?
When Buffet says he sold all of his Walmart stock.... who did he sell it to? I doubt it was Joe Blow... so clearly its another institution. Is an ETF fund even an institution? They are obviously buying and selling to balance their funds, but maybe these funds are owned more so by retail... who knows.
So really, institutional volume is almost useless since you don't know who is buying, for what purpose, and if they are buying for themselves or their clients. (heck, it might even be as a hedge where they don't care if it goes up or down).
Now in terms of block trades, its very similar. Clearly there might be a different depending on what instrument we are talking about, but from my understanding when it comes to futures, trades can easily come in as a serious of 1 lots spread by just a micro second. In addition to this, I think I even saw some rules about how exchanges can group a bunch of trades together and lump them as 1 trade, to make it look like a large block, but really, it could just be made up of lots of little trades.
I've seen lots of videos where traders try and guess institutional volume by having their platform only display trades above a certain size, like 47 or what have you in the ES, and they constantly change this number as if they supposedly cracked the code of how many units the institutions are trading in that day. Who knows, maybe they are onto something, but with so many variables, its really hard to tell.
So back to the OP, the question you ask is very difficult to answer, and there might not even be an answer because you will never know.