Table: schools_auckland
Columns: name
years
gender
area
authority
decile
roll

Question: How many values for decile occur in Mount Roskill with Monte Cecilia school with a roll greater than 170?
SQL: SELECT COUNT("decile") FROM schools_auckland WHERE "area" = 'mount roskill' AND "name" = 'monte cecilia school' AND "roll" > 170