Thanks all.
The problem with converting to Excel is that the worksheet will lose some of its functionality.
For example; Numbers allows multiple Tables in a single worksheet. Each can be re-sized and moved to any convenient location within the worksheet. This is not possible with Excel.
In the example below I have moved the position of a separate Table (indicated by red arrow).
Even though Excel has many more functions and formulas, Numbers appears to offer more flexibility and options regarding the way the information is presented. The problem with Numbers is not being able to password protect cells containing formulas.
So to have a worksheet like this, I might have to get involved with ios application programming.
