maybe the factor why the price of bitcoin has an up and down price movement is probably because of the information circulating in some media and for rising prices usually due to good news.
It is not depending upon good news but the real thing is market demand, now the good and bad perception has gone. Now we are just thinking and focusing on investments in order to make our output which will be better if it is Bitcoin.
Just look at the demand graph and notice increase in price after noticing increase in market demand. The price will go up and down with alteration in demand rate.