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_6 ( population_density VARCHAR, name VARCHAR, change___percentage_ VARCHAR )

### Question ###
What is the population density of Siglunes when the change was smaller than -8.1 percent?

### Accurate SQL ###

SELECT COUNT(population_density) FROM table_name_6 WHERE name = "siglunes" AND change___percentage_ < -8.1