Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_22815568_2 ( unemployment_rate VARCHAR, market_income_per_capita VARCHAR )

### Question ###
What is the unemployment rate for the county with a market income per capita of $20,958?

### Accurate SQL ###

SELECT COUNT(unemployment_rate) FROM table_22815568_2 WHERE market_income_per_capita = "$20,958"