Can someone please help me create a count funtion in a very simple report that I have created?

I would like the function to tell me how many times the steam pressure is between 80 and 100 psi at a minimum of 4 consectuive hours. The attached jpeg shows the data with four instances circled in red. The data being pulled is date/time and steam pressure for a prticular furnace run.

Any help would be much appreciated. I am new to BO so please explain your solution in simple terms!

Thank you!