Ratios in matrix | Matrix/Vector | if statement/loop |

I was wondering how would you explain below function to work with matrix instead of vector input, essentially I just find all values that is over a certain value in that column and add it up and divide it by total rows to give me ratio. Below is working for vector input but I kinda not sure how to complete the one with matrix input. Should I use logical instead?

The method I chosen don't think will work if there is more than 2 columns but I wish it could accommodate any size.

function Ratio = ratiovector(Vector)

N = numel(Vector);
c=0

for a = 1:N

    if Vectors(a) >= 20
        c=c + 1;
    end
    end


Ratio = c/N;
end

Matrix Input

function Ratio = ratiovector2(Matrix)

rows = Matrix(:,1)
columns = Matrix(:,2)
c = 0
d = 0

for a = 1:rows
    for b =1:columns

    if Matrix(a) >= 20
        c= c + 1;
    if Matrix(b) >= 20
        d= d + 1;
    end
    end


Ratio = ?;
end