Thanavath Phonvichai, director of the Centre for Economic and Business Forecasting at the University of the Thai Chamber of Commerce, said the CCI in February stood at 69.9 points, down from 71.5 in January.
The index has dropped for 11 months consecutively and fell to its lowest point for 12 years this month, or since 2001, he said.
The overall economic index dropped to 59.7 points from 61.4 in January while the job opportunity index stood at 63.6, compared with 65.1 in the first month of the year.
The future income index meanwhile fell from 88.1 to 86.3.
The CCI combines indices measuring sentiment on the economy, job opportunities and future income. A score of 100 is considered normal.