A company's sales in 2019 were $4.1 million and its total spontaneous assets were $3.1 million. Also in the same year, the firm's spontaneous liabilities consisted of $0.19 million in wages payable, $0.21 million in accounts payable, and $0.09 million in accrued expenses. The firm's profit margin is 2.92% and its dividend payout ratio is 48.72%. The balance sheet at year-end is similar in percentage of sales to that of previous years and this will continue in the future.

Required: What is the percentage increase in sales that the company must achieve in order to avoid raising funds externally?