Question : Most common occurance

How can I determin the most common occurance of numbers in a table? and the number of times they have been recorded in the table
the table is filled with numbers anywhere between 1 - 20.
dDate     | wnum |
1/1/10        2
1/1/10        5
1/1/10        8
2/1/10        5
2/1/10        1
2/1/10        19
2/1/10        5
3/1/10        1

most common is '5' 3 times
2nd is '2' 2 times

Im using access and asp

Answer : Most common occurance

txtBox1= DMax ("field","table") + 1