The issue with multiplying 1.1 times the number of years would be huge. multiply 1.1 times 5 years and that would be an increase of 5.5 times the size. Or rather 550% larger
In excel we can calculate the new area and parameter and get it pretty close. I just tried it and the 5th year was very very close to doing the whole thing five times.
3 columns.
Row 1 Len(A1) Area(B1) Buffer(C1) The first values for Len and Area come from you polygons. the first buffer is
=((B2*1.1) -B2)/A2 this will fill in C2
A2 and B2 came from the polygosn
for cell A3 =A2 * (1 + (C2/100)) then drag it down
for cell B3 =B2*1.1 drag it down
for cell C3 drag C2 down
I did this with my example. By creating 5 buffers in ArcMAP the final increase was 3.939114292 by running this trough Excel I came up with 3.939114202
So I would think if you export your polygons with ObjectID, shape length and shape area you can calculate the 5 and 10 year buffer sizes rather quickly. then you can bring the table back in and with a join populate the 5 and 10 year buffers.
However, I would say in Access we could build a calculation that would add up the new area and length and in a single iteration calculate the final buffer for 5 and 10 year.