I'm having difficulty developing a spreadsheet to analyse specific data that I'm interested in and would appreciate if someone could help me out.

I have 24 hourly data for 365 days, thus giving me a total of 8760 results. However, I'm only interested in processing data that are between the hours of 08:00 and 18:00 Monday to Friday for the year.

I don't want to account for data outwith these hours and for those occurring during the weekend.

The purpose of my analysis is to determine the number of hours during air handling plant operation whereby the air heating load falls below 87kW. I have used conditional formatting to highlight cells red where this occurs and then IF function to identify Heating Load < 87kW? (0=No, 1=Yes).

The idea here is that I can then sum up the total number of hours of plant operation (08:00 to 18:00 Monday to Friday for the year) and compare this total operation hours with the number of hours where the air heating load falls below 87kW. I can then determine the percentage of hours where this occurs.

I would also like to develop an annual graph that then allows the data to be shown for the year that identifies space heating periods and summer months.

I've tried to work this out myself and I'm struggling to progress further. I'm not looking for anyone to do the work for me, but would very much appreciate if someone can help out with some suggestions.