Ok,no funny business here guys,i'm not talking downstairs.
What kind of size is worth taking note of in the YM and ZB?
In other words if i was watching the tape in either of these markets,what would make me go..."Wow,that's BIG!!".
I realise that in certain market conditions there may be a considerable spike to the average,but in terms of 'normal' market conditions what should i take note of.
I appreciate any comments anyone can offer.

Cheers,
sk