The 2014 WTA Finals held no doubles tennis competitions.
 The WTA then decided to adopt a JanuaryNovember playing season, and so the event was switched to being held at the end of each year
==== Singles and doubles professional careers ====While players are gradually less competitive in singles by their late 20s and early 30s, they can still continue competitively in doubles (as instanced by Martina Navratilova and John McEnroe, who won doubles titles in their 40s)

