Money owed to you is the total customers have been invoiced for but have not yet paid. In accounting it is called accounts receivable.
It is earned but unavailable. A large figure here alongside a small cash balance is the most common reason a business with steady work still struggles to make payroll.
Ageing
Omnyra tracks invoices more than sixty days overdue separately. Collection rates fall the longer an invoice goes unpaid, so the age of the balance matters as much as its size.