IMHO a more accurate account would be close to 100% loss over the year ending December 31 2020. GDP for the whole of Thailand is not but 505 Billion dollars. Also I would bet 20% is tourist money.
So about 1/5 of all money is lost. And that is last years GDP. Other things such as lost domestic sales and revenue will also be dramatically down.
The door will open even wider now for China.
My opinion would be to get out of Thailand as soon as possible. You guys hanging on better brace yourself's for some rough times ahead.