I guess MS' statement means that PS4 outsold the XBox One by less than 266.2k but more than 243.6k in the last 2 months (otherwise they could have said outsold ps4 for the last 7 months of the year)
XBox One vs PS4
Jan: -97k
Feb: -156.7k
March: -88.6k
April: -7.2k
May: -100.2k
June: -22.6k
July: +9.9k
August: +114.8k
September: +47.5k
October: +94k
November: -100k ?
December: -166.2k < x < -143.6k
So PS4 extended its lead in 2016 by anywhere between 349.7k and 372.3k units, if I got my numbers right.