In 2011, average UK weekly expenditure rose to £483.60, an increase of £10 from 2010 and the highest recorded, according to the Office of National Statistics.
More top news
Other entries in the UKTV channel Gold competition included jokes about Donald Trump, Brexit, Southern Rail and Ryanair UKTV channel Gold.
Temperatures will remain close to freezing.
The prime minister's announcement came as international leaders gather in Paris on the second anniversary of the climate change plan.