Trigger should not alarm until certain number of data collected

[anc322]

Hello, can you suggest how to create such trigger:
I have an item that gets polled once an hour
I do not want my trigger to be in alarm until I collect n values, or for some time period.
I have tried something like
max(#31)}<0 but it sets alarm already after 1st check.
I have also tried max(5d)<0 also with no luck

any suggestions are much appreciated,
thanks,
Igor.

[anc322]

there is a count() function, if I use count(1d)>20, will it trigger only if there are more than 20 values per day collected ?