Calculate percentage increase of a stock value?

Question

If I buy a stock for $100.00 and it appreciates to $200.00, what is the best formula to calculate the % increase?

(200-100)/100

or

(200-100)/((200-100)/2)

Answer 1

(200-100) / 100 = 100% increase

Answer 2

enable's say it replace into one hundred factors and went right down to 80, that could desire to be a 20% shrink. So it might could desire to strengthen by skill of 20/80 or 25% to make up the adaptation. hi MEGABRAIN JUDY! the marvelous answer IS 25%!!! be chuffed to ask somebody in the adventure that your hardship-unfastened innovations gets puzzled back.