How to calculate Sales per Square Foot

Formula

Sales per square foot = store sales ÷ selling area (square feet)

SQL query

This example assumes: stores(id, name text, selling_sqft numeric), store_sales(store_id bigint, sale_date date, amount numeric). It is written in PostgreSQL syntax; date functions differ slightly in MySQL, BigQuery and SQLite, and your column names will differ from these.

SELECT s.name,
       SUM(ss.amount) AS sales,
       SUM(ss.amount) / NULLIF(s.selling_sqft, 0) AS sales_per_sqft
FROM stores s
JOIN store_sales ss ON ss.store_id = s.id
WHERE ss.sale_date >= CURRENT_DATE - INTERVAL '12 months'
GROUP BY s.id, s.name, s.selling_sqft
ORDER BY sales_per_sqft DESC;

Common mistakes that make Sales per Square Foot wrong

• Use selling space, not total floor area; stockrooms and offices are normally excluded.
• Stores open for part of the window need their sales annualised or excluding from the comparison.
• The same calculation works per square metre; keep one unit across all stores.

Ask for Sales per Square Foot in plain English

Instead of writing the query yourself, you can type the question. SchemaChat turns it into SQL against your connected database or uploaded file, runs it, and shows the SQL and the figures it used so you can check the answer before you share it. It does not replace your judgement about the definition: check that the query matches the formula your business uses.

• What are the sales per square foot for each store over the last 12 months?
• Which stores earn the least per square foot?