Percentage change

[xeven_]

I have this formula in column N and it is looking at price in column E. =(E2/$E$2-2)
My objective is to keep a running tally of the stocks accumulated percent change from the first cell entry.When I enter this in excel 2016 and the first cell entry is 0.78 and the last is 13.55 it is giving me the figure 1,540% however when I use an online percentage change calculator it is giving me a different value i.e. 1,637% for the same numbers. Does anyone know what is going on here? I want my results to be as accurate as possible, not giving two different outcomes.

 

[steve the fish]

Whats the 2 for? Anyway id have thought its:

=(E2-$E$2)/$E$2

 

[xeven_]

Thanks
I put =(E2-$E$2)/$E$2 in O1 the value in E1 is 0.78 and the value in E252 is .80, with this formula it is giving the result of 3.21%. The online percentage change caluator: https://percentagecalculator.net/
is giving me 2.56%.. I am not sure what is going on here, I dont think it is a decimal issue either.