Chances of getting a female riolu when mating a male lucario and a ditto?

Question

I have been spending hours and hours trying to get a female riolu by breeding the only lucario I had with a ditto. And unfortunately that lucario was a male. I would appreciate if anyone could tell me what the chances are to get a female riolu.

Comments

When I bred my male Lucario with my Ditto I got 2 female Riolu´s right off the bat. I was so lucky!

Answer 1

The chance of hatching a Female Riolu is always 12.5%. (Which is a 1/8 chance)

Source

Answer 2

87.5% male, 12.5% female
http://pokemondb.net/pokedex/riolu