user: Question: What is the population density (per km) that has -6.7 as the change (%)?
Columns: ['Name', 'Population (2011)', 'Population (2006)', 'Change (%)', 'Land area (km²)', 'Population density (per km²)']
Types: ['text', 'real', 'text', 'text', 'text', 'text']
Sample row: ['Black Point', 47.0, '—', '—', '—', '—']
SQL:

assistant: SELECT "Population density (per km²)" FROM "Table" WHERE "Change (%)" = '-6.7';