There is no explanation needed. Population of the study shows aprox 50% of people in working age is man, 50% is women. If no ties, allegations, recrimination or social constructs were given (no sex-discrimination) the experiment for a big enough population will give aprox. 50% of each genders being programmers. As result of experiment shows contrary, the function that determines the posibility of access to "work as a programmer" is not "random/no discriminatory". Sorry mate, the only one who has given no explanation is you, "you are tied to recriminate sexism" is your only crybaby argument.