Like TSMC, who provide chips to Bitmain, they prominently blamed some of their losses to the downturn in demand for cryptocurrency. Less demand amounts to less need for mining, which lessens the demand for mining hardware.
Co-president Jason Wang said:
“Looking into the first quarter of 2019, we anticipate further deceleration in customers’ wafer demand, due to a softer than expected outlook in entry-level and mid-end smartphones as well as falling crypto currency valuations. Although UMC’s ongoing transformation will need time to reach its full synergy and potential, our progress so far has enabled the company to better endure these current headwinds.”