CREATE TABLE table_22815568_1 (poverty_rate VARCHAR2, market_income_per_capita VARCHAR2)

What is the poverty rate in the county that has a market income per capita of $16,420?
SELECT poverty_rate FROM table_22815568_1 WHERE market_income_per_capita = "$16,420"
SELECT "poverty_rate" FROM "table_22815568_1" WHERE "$16,420" = "market_income_per_capita"