I'm a little bit confused about stating exponential growth.

Question

We have a growth factor which is stated as 1 + the rate it's growing as a decimal.
So I have a table like this:
x y
1 2
2 6
3 18
4 54
5 162
6 486

I can see that my "y" is growing 3 times each time the "x" goes up by 1, or tripling. So how do I state my growth rate?
If tripling is 300%, that would be 13.00 as a growth rate (1 + the rate as a decimal), but that doesn't come out correctly either -- 54 x 13 = 702, now 162, etc. I'm so confused!

Answer 1

y = 2/3 * 3^x

Answer 2

this isn't a growth factor?

Answer 3

since it triples every year, that's a 200% per year growth rate.