Why does the fare on flights with ryanair keep changing?

I looked online and saw that a flight for next october would cost me 86.72 but then when i checked again the next day i saw that it had gone up by double the price! i checked it on other flights and the same has happened with other flights they keep changing!!! will it go back down again when the time comes closer or am i going to have to pay it??? I eally dont want to pay nearly 200 for a day trip!Why does the fare on flights with ryanair keep changing?Thats how airlines work- cost of tickets are dependent on several factors- cost of gas at the time, and more importantly- how many people book tickets for that route. Its supply and demand. You can wait to buy the ticket a few months- keep checking prices every week or so- its a big game!! You have time right now to wait and see what happens.