How to get the run time percentage from the count in Salesforce?

Hi All,

I have a mutliple fields which holds the count of the each value selected in the records.

for example i have multi picklist which have the values A,B,C,D.

I have four records,

Record 1-A,Record 2-B,Record 3-A&B,Record 4-C.

Fields hold the count as like below

Filed1__c=2(A's), field2__c=2(B's),field3__c=1(C's).

Here my requirement is, I want the percentage of each count at run time.

How to form the query?

Thanks in advance