Oasis Petroleum Inc. (NYSE: OAS) launched a new stock offering to partly fund its 2016 capex of $385- to $435 million, even though its budget is about 30% lower than last year.

The North Dakota oil producer said on Jan. 28 it would offer 34 million shares, with a 30-day option for underwriters to purchase an additional 5.1 million shares.

Based on its close on Jan. 27 of $5.32, Oasis can raise as much as $208 million from the offering, including the underwriters' option.

Oasis Petroleum shares fell as much as 15% in premarket trading to $4.51. The stock has more than halved in the past year.

The company said it expects to produce 46,000-50,000 barrels of oil equivalent per day (boe/d) in 2016, compared with 50,477 boe/d last year.

About 60% of Oasis's oil output has been hedged at an average price of $53.36, the company said in a statement.

U.S. crude was trading at about $32 on Jan. 28.