“…Others, for example Edge & Wilson (1990) and Simian (1987), have developed rules and procedures that should be followed to ensure the accuracy, consistency and completeness of spreadsheet models. Despite experimental studies that have shown that spreadsheet errors are difficult for people to detect and correct (Galletta, Hartzel, Johnson, Joseph, & Rustagi, 1996;Panko & Sprague, 1998) it is generally recognised that spreadsheets should be audited and tested using a formal process (Berglas & Hoare, 1999;Whittaker, 1999). An audit of a complex set of spreadsheet-based models developed by the Australian Department of Immigration to examine the effect of immigration on the government's budget revealed over 250 problems and issues which were corrected before the model was used (-, 1999).…”