NEW YORK (TheStreet) -- Oilfield services giant Halliburton is optimistic about its future, despite the tumbling crude prices, but analysts see a major challenge ahead with a possibility of oil falling to $75 a barrel in 2015. The Houston-based company released its third-quarter results on Mondayashowingarevenue climbed by 16% from the same quarter last year to $8.7 billion due to higher drilling activity in North America and strong growth in international markets.