I've hatched 3 Shinies in my life, a 5iv Brave Honedge, a 5iv Modest Mareep, and a 5iv Sassy Zorua. Honedge I hatched about 400 eggs if I had to guess, Mareep was about the same, and Zorua was in about 30. (Unfortunately, I was trying to breed for the right nature at the time, so that's...