I thought I should mention that my new book is out, The Year's Best Science Fiction and Fantasy, 2016 Edition. It's always fun to see the book in print, and to celebrate a whole bunch of great stories.
I dedicated this book to my late father, John Richard (Dick) Horton.
Apropos of that, I recently put together a spreadsheet detailing all the contributors to my books over the past 11 years. This series began in 2006 as two books: Science Fiction: The Best of the Year, 2006 Edition; and Fantasy: The Best of the Year, 2006 Edition. There were three years in that format, and in 2009 we switched to the bigger combined format, with both SF and Fantasy. (I should note that each edition -- 2006, 2016, whatever -- collects stories from the previous year.)
So here's this year's cover:
And I think the statistics back me up. Bottom line -- 62% of the stories in all my books combined were by writers who were appearing first in that year's book. But that's distorted, because of course for the first few years most of the writers were, by default, firsts. The numbers seem to settle in around 50% new writers each year beginning in about 2011 -- the percentages from 2011 through 2016 are 54%, 43%, 61%, 49%, 29%, 53%, 62%. The cumulative total percentage since 2011 is 48% new writers.
So, about half the writers in a typical book of mine have never before appeared in one of my Best of the Year collections. That seems pretty good! And, in fact, a quick comparison with at least one other editor suggests that my percentage of writers new to me is significantly higher. (Which isn't to say the other books aren't also excellent -- they are!)
One more set of numbers: I have published 354 stories by 219 writers over the 11 years of this series. 143 of those writers have appeared in my books only once. The writers who have appeared most are Robert Reed (10), Elizabeth Bear (6), Kelly Link (6), Theodora Goss (6), C. S. E. Cooney (5), Yoon Ha Lee (5), Holly Phillips (5), Genevieve Valentine (5), Rachel Swirsky (5), and Peter Watts (5). (Some of these totals might be slightly affected by how I treated collaborations.)