Israel ranks as the 11th happiest country in the world - ahead of the US, at 15, and the UK, at 21 - according to the 2015 World Happiness Report published last week.

Switzerland triumphed in first place, followed closely by Iceland, Denmark, Norway, Canada and Finland, all of which are also among the richest countries in the world. The ten unhappiest countries are in Saharan or sub-Saharan Africa, as well as Syria and Afghanistan.

Many Middle Eastern countries were placed towards the bottom, with Egypt at 135, the Palestinian Territories at 108, and Lebanon at 103.

The study of 158 nations was compiled by a group of international academics, including Jeffrey Sachs of the Earth Institute at Columbia University, John Helliwell of the University of British and Richard Layard, the director of the Well-Being Programme at London School of Economics.

"Countries below that top group fall short, either in income or in social support or in both," explained Mr Sachs at a press conference announcing the results. "One of our very strong recommendations is that we should be using measurements of happiness... to help guide the world during this period towards the new sustainable development goals."

Inspired by Bhutan’s initiative to measure “gross national happiness”, UN Secretary General Ban-Ki Moon spearheaded the annual ranking project in 2012.

Some of the factors considered are GDP per capita, healthy life expectancy, lack of corruption, generosity and the feeling of having someone to depend on.