Hey, I got hold of some interesting data from Audit Analytics on the length of time that some US companies have had the same auditors.

The issue arises in connection with a CFO cover story on audit fees that I wrote about yesterday.

The article explains how CFOs are putting pressure on auditors to lower their fees after they climbed steadily in the wake of the Sarbanes Oxley Act. And that naturally requires some shopping around, which until now has been done primarily through requests for proposals.

As the CFO of one such company told Tim Reason, my former colleague and the editorial director of CFO.com, his company was trying to cut costs across the board, and it had had the same auditor for 40 years, so that was a prime potential source of savings.

Money quote: "After 40 years, everything should be put out to rebid."

So one naturally wonders what other companies might have such an opportunity. As it turns out, Procter & Gamble has the longest uninterrupted relationship with its auditor, according to Audit Analytics. P&G has used Deloitte for three times that long, that is, ever since 1890.

Other big-name companies whose relationships with their auditors date back well longer than four decades include General Electric, which has been with KPMG since 1909, Coca-Cola (Ernst & Young since 1921), Caterpillar (PwC since 1925), and Goldman Sachs (PwC since 1926).

Of course, it's possible those companies have put on RFPs from time to time to see how their audit firms' fees stacked up, but given the ever dwindling number of big auditors, we somehow doubt they bothered to do so.

Still, SarbOx has put an end to the use of audits as a loss leader for consulting services, so it may be long past time for those companies to start. CFO's handy new tool makes it easier. But CFOs who don't want to spring for the $1,200 fee should at least get some RFPs out the door.