Thai people were significantly less happy last month and it was due mainly to escalating violence in the deep South, according to a poll.

The Abac Poll Research Centre's gross-happiness index plunged by more than 20 per cent in July.

The index registered 7.29 points of a possible 10 - down 21 per cent from 9.21 points a month earlier during the euphoria of celebrations for the 60th anniversary of His Majesty the King's accession to the throne.

However, the people's love for their King and an appreciation of their culture continued to keep general happiness levels "satisfactory", poll centre director Dr Noppadon Kannika said.

"From our statistical analysis we found the main factors affecting gross happiness were loyalty [to the monarchy], unity and love among fellow countrymen, Thai culture and tradition, as well as local environment," Noppadon said yesterday.

The happiness survey was conducted in 26 provinces between August 1 and August 12, questioning 4,533 respondents.

According to the survey, celebrations for His Majesty's jubilee continued to bring happiness to 91.1 per cent of respondents.

And, 95.3 per cent were delighted about royal projects.

National culture, values and tradition kept 88.8 per cent happy.

Religious teaching and morality kept 88.4 per cent buoyant.

At the same time, 89.3 per cent were sad about unrest in the deep South. That figure was just 67.4 per cent in June. That was a 24.5-per-cent rise.

Noppadon said moves by the Supreme Court to tackle the political crisis appeared to have improved people's happiness slightly.

The July survey found 78.7 per cent were happy with the judiciary.

A majority of respondents remained generally unhappy with politicians, the government and independent organisations.

Just 34.6 per cent were happy with the level of ethics shown by these groups and, when it came to rating their honesty, only 28.3 per cent could claim to be happy.

Rising petrol prices were putting a frown on almost everyone's face with just 6.4 per cent claiming they weren't bothered.

The rising cost of living was depressing 67.3 per cent of respondents.