Dynamic function - Excel

Dynamic function - Excel

i have a dataset with variable and its frequency; based on that i need to
calculate frequency percentages. Ranges to be considered for the variable
are:
1-2
3
4-5
Now, suppose if frequency count of "5" is missing then the formula should
work dynamically and calculate the frequency percentages accordingly
Example: X 1 2 3 4 5 Total
Freq 5 6 8 9 10 38
1-2 3 4-5
29% 21% 50%
X 1 2 3 4 Total
Freq 5 6 8 9 28
1-2 3 4-5
?? ?? ??