Well most of that decrease was because of the correction and the recent crash was because of the news referring the incident regarding the Cryptocurrency exchange in South Korea had been hacked by some unknown individuals, Well on your statement with the recent value of bitcoin I really think the price will keep on doing that, And involving the cost for bitcoin or in my understanding I really think if you are referring to the fees of bitcoin right now it is sure are increasing or if you are referring with the mining it is always affected the value of bitcoin each time another block was found or the resource needed towards it increases.