Thai tax deductions

Excerpt from BOI website:

Other types of taxable income and the rate of standard deduction include:

• Interest, dividends, capital gains on the sale of securities: Forty percent but not exceeding 60,000 baht.

• Rental income: Ten percent to 30 percent depending on type of property leased.

• Professional fees: Sixty percent for income from medical practice, 30 percent for others.

• Income derived by contractors: Seventy per cent.

• Income from other business activities: Sixty-five percent to 85 percent depending on the nature of the business activity.  

QUESTION?

Anybody know what the classification is for the last category.

What "business activities" warrant 65 and what ones warrant 85%. What are the divisions in-between 65 and 85%????