Percent Null in Row Generator

[dspxlearn]

Hi all,


I was using rowgenerator for generating some test data.So i was generating 100 rows with two columns..col1,col2.where col1 is of datatype integer and nullable.So,while editing the col1 and giving options Percent Null as 10..i believe it should return 10% of the output data as null values..but it is showing 14 records as 'NULL'.And if i give Percent Null as 20 it is returning 30 records with 'Null' values...What might be the reason for this...