I have a workbook which shows salaries for a number of employees over the
last 10 years. I need to find the average of the three highest consecutive
salaries over that period. The columns are ordered by date so it is not
possible to re-order each row.

2005 2006 2007 2008 Ave
Emp 1 10,000 11,000 12,000 13,000 12,000
Emp 2 13,000 13,000 14,000 10,000 13,333
Emp 3 13,000 12,000 11,000 10,000 12,000

Any help would be grately appreciated!
Dan