Why do you have 9 factors? The classical Drake equation has 6 (and the L which is the avg. lifetime of the civilization). Also: The Drake equation has one fact

Why do you have 9 factors? The classical Drake equation has 6 (and the L which is the avg. lifetime of the civilization). Also: The Drake equation has one factor which is the avg number of planets per star, of which we are already quite confident it is above 0.1.