The following financial statement data are taken from Xeron Company's 2006 annual report:
(in millions)
Current assets $12.6
Investments 9.4
Intangibles 6.8
Tangible assets (net) 58.1
Current liabilities 6.4
Long-term debt 39.7
Stockholders' equity 40.8
Compute the debt to tangible net worth ratio.