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_name_8 ( population_density__per_km²_ VARCHAR, change___percentage_ VARCHAR )

### Question ###
What is the population density (per km) that has -6.7 as the change (%)?

### Accurate SQL ###

SELECT population_density__per_km²_ FROM table_name_8 WHERE change___percentage_ = "-6.7"