This year's color for queen marking is indeed yellow.  The color scheme
is:
White  for years ending in 1 and 6,
Yellow for years ending in 2 and 7,
Red    for years ending in 3 and 8,
Green  for years ending in 4 and 9 and
Blue   for years ending in 5 and 0.
 
There are two mnemonics to help in remembering this:
"When You Requeen Get the Best!" or "What!? You Raise Green Bees!?"
Personally I like the green bees, but I always try to get the best!
 
Aaron Morris - thinking it's time to grow my own!