It also stretches its lead over the Xbox One to 2/3rd of a million - Which is what the Xbox One will be lucky to achieve this year if it continues its steady decline at this rate.
Xbox One is slightly ahead of 360 in 2015, which did 930k for the year.
If it keeps the same pace of declining it should reach 1 full million by end of the year, what 2/3rds are you talking about ?
And no, it is not luck, it's something normal. Even the 1M this year is something normal. More than 1M for the year will be luck.