The Christmas fortnight is so stuffed with sporting fixtures that it can make a material difference to the bookmakers’ final quarter results, especially as many end their financial year on 31 December.
Christmas 2013 was a mixed one for the bookmakers.

The results in the English Premier League were not so good. Manchester City played three and won three, as did Manchester United (although when they were 2-0 down to Hull, it was looking like a gift for the bookies). 

Arsenal won twice and drew 0-0 with Chelsea, which would have helped the sports books. Liverpool lost twice albeit to other Big 4 teams in Chelsea and Manchester City.
The other element of the Christmas fixtures was they were high scoring. 
19 out of the 30 (63%) games had more than 2.5 goals, which is above the long term average.
The new year did not start much better for the bookmakers with Man City, Liverpool, Chelsea, and Arsenal all winning. 
In the Ladbrokes World Darts Championships the favourite Phil Taylor was knocked out by Michael Smith even before the Christmas presents had been wrapped. Taylor was 66/1 on for the match and was still trading at 4/1 on in the final set. 
Pricewise was on good form in the Racing Post over Christmas with winning selections like Willow’s Saviour (16/1 in to 10/1 in the Ladbroke Hurdle) and Silviniaco Conti (5/1 in to 7/2) in the William Hill King George VI Chase.
2013 Gold Cup winner Bobs Worth (11/4 jf) returned to form in the Lexus Chase at Leopardstown, whilst Hurricane Fly won the Ryanair Hurdle at 11/10.
The favourites all won in the four televised races from Cheltenham on Channel 4 in New Year’s Day, albeit some at short prices: 5/6, 7/2, 11/8, and 2/5. 
GBGC director Lorien Pilling commented, “There had been an element of unpredictability in the Premier League so far this season but unfortunately for the bookmakers the games became much more predictable over Christmas. The racing results were generally more favourable for the layers, although having Pricewise tip several winners on the big racing days would have dimmed the bookmakers’ festive glow a little.”