...oblem is that spreadsheets contain an unexpected and unacceptable number of errors. We know this from the results of both field audits of actual business spreadsheets and from laboratory experiments [=-=Panko 2000-=-]. Field audits since 1997 of 54 spreadsheets found that 91% contained errors. Most of these were classified as "major errors" or "spreadsheets were off by at least 5%." Eighteen laboratory experiment...