Total Assets are Balance Sheet entries reflecting the value of anything owned by a business that could be converted to cash. This would include Cash, Receivables or money that is owed to the business including money owed by clients that have purchased products or received services but have not paid yet. Inventory plus Net Fixed assets like equipment and buildings are some of the accounts included in Total Assets.

In this case, Total Assets is calculated by the average of the last 3 months of Total Assets. Being that Assets are a snapshot in time, using the average of the last three months will smooth out large monthly variations.

Sales or Revenue is the number reflected on the Income Statement representing total income over any given time period. Many call this the "Top Line".

In this Metric Ratio, Sales is an annualized number calculated by adding up the last 3 months and then multiplying it by 4. Using the last 3 months for sales rather than the whole prior 12 months will allow the Sales to Assets ratio to respond faster than it would if the whole prior 12 months were included in the calculation.