Hi Sarah

To answer your question well it would certainly help to know why the area of 
the polygon needs to grow by a value and indeed what the polygon represents.

I have listed below one technical solution but before that I would just like to 
show some caution by suggesting for most applications this would be a dangerous 
assumption.

If a planning authority decided to allow a 10 per cent growth in housing it is 
highly unlikely they would allow a uniform growth. There would be many 
constraints. Physical constraints such as rail, river and road and 
environmental considerations would make the following a meaningless solution.
The growth is just as likely to be a bubble on the side of the existing area as 
a uniform growth as detailed below.


With that reservation in mind:-

One solution...

Find the existing area by one of MapInfos alternatives ... eg using select tool 
select object.

In a similar way find the perimeter of the object. Multiply the area by the 
percentage increase to get the increased area.

Divide the increased area by the perimter to find a buffer value.

Buffer the object with the offset as calculated.

This solution to be very accurate would need to be iterative. The new object 
would not exactly be the correct new area because on obtuse angles around the 
perimeter it will increase too much and on acute by not enough. However if say 
you wanted to increase by 10% and your first calculation for the offset is say 
9.2 metres and this gives a real increase of 11% your second iterative solution 
for the offset would be 9.2m x 10/11. ( hope this makes sense ).

This technical solution is of course based on increasing the object out from 
its centre uniformly by a constant buffer size and I cannot straight off think 
of an application where this would be apporopriate!

Regards


Bob





Quoting Hooper Sarah <[EMAIL PROTECTED]>:

> Hi,
> 
> I am trying to increase polygon sizes by a percentage value. How do I go
> about this? And is there a way to increase many at once?
> 
> Thanks in advance,
> Sarah
> 
> 
> 
> 
> 
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