COUNT based on categorized criteria(priority basis)

HI Power community,
This is my first post ever:

I have this table visual in my report and the highlighted cloumns are the categories that need to be considered in this post.
Please note actual data has thousand of rows , here I want to count no of occupier that lie in a category(Mentioned below) and once an occupierID is counted in a category, it should not be counted in other category.

EXPLANATION: the severity (highlighted columns) are assigned based on the occupiers so the counter should count like this

Number of occupier for tenant ABC where:
RISK Severity Level = "Extreme" && Severity Trend = "Deteriorating"
RISK Severity Level = "Extreme" && Severity Trend = "Steady"
RISK Severity Level = "Extreme" && Severity Trend = "Improving"

RISK Severity Level = "High" && Severity Trend = "Deteriorating"
RISK Severity Level = "High" && Severity Trend = "Steady"
RISK Severity Level = "High" && Severity Trend = "Improving"

RISK Severity Level = "Medium" && Severity Trend = "Deteriorating "
RISK Severity Level = "Medium" && Severity Trend = "Steady"
RISK Severity Level = "Medium" && Severity Trend = "Improving"

PLEASE NOTE that my requirement is to count the occupierID only Once in this counter and priority of counter is it should count like above mentioned sequence (extreme first , then High then medium{and second catogory also in same sequence as mentioned}...)
OutputS of above table would look like this

Please i need the best possible way to achieve this outcome.

THANKYOU