user: Question: What is the average area in square miles for the hunan administrative division with a national share less than 2.19%?
Columns: ['Rank', 'Administrative Division', 'Area (km²)', 'Area (sq mi)', 'National Share (%)', 'Comparable Country']
Types: ['text', 'text', 'real', 'real', 'real', 'text']
Sample row: ['1', 'Xinjiang', 1664897.0, 640900.0, 17.23, 'Iran']
SQL:

assistant: SELECT AVG("Area (sq mi)") FROM "Table" WHERE "Administrative Division" = 'hunan' AND "National Share (%)" < 2.19;