I have been attempting to group countries based on the percent of total. So if the you have 6 countries, then you group top 2 values together, the middle 2 countries together & the bottom 2 countries together.
Suppose the order from top to bottom:
Saudi - 6,000,000
China - 5,000,000
Singapore - 4,000,000
Australia - 3,000,000
India - 2,000,000
New Zealand - 1,000,000
Saudi & China would be grouped together (Top 2), Singapore & Australia would be grouped together (Middle 2) and India & New Zealand (Bottom 2).