"O + (N x S) + Cpm/T + He" is a formula developed by Cliff Arnall, former tutor and research psychologist at Cardiff University, to determine people's happiness.
The formula takes into consideration, among other things, outdoor activity, social interaction or temperature.
“We did a piece of work a couple of years ago, and we developed a survey of 50 questions. So you can really go into some details,” Charles Seaford, head of the Centre for Well-Being at the New Economics Foundation, told CNBC.
“You can ask people how happy they were yesterday. These are the things that the government will be doing. How happy people were yesterday, how satisfied they are with their life overall, how worthwhile the things they’re doing in their life are, and how anxious they felt yesterday,” he said.
But this type of index or the use of gross domestic product (GDP) to determine happiness cannot explain everything, Seaford said.
He said this was evident in the "Easterlin Paradox".
“What it shows is that at a significant time, the more money you’ve got, the more happy you are,” said Seaford. “But if you take a country as a whole, over a period of time, GDP may rise, but the level of happiness in the country as a whole doesn’t rise.”
This could be explained by the fact that relative income is what actually matters, he said. "You’re happy because you’re better off than other people. You have access to things few people can have. But of course, if GDP goes up, your relative income may not increase at all,” he said.
But are these indices actually reliable? Caroline Lawes, research team manager at ComRes, cast some doubt on Seaford's formula.
“Since October last year until now, the country’s happiness hasn’t changed one bit,” she said.
“So we’re seeing about 80 percent of the population say they’re pretty happy. And even when their concerns about the economy have gone down, even when they’re worried about job security, even when it’s Christmas, actually, their happiness hasn’t changed at all," she said.