Nigerian oil and gas exploration and production company Seplat Petroleum announced on Thursday that its 2014 pretax profit dropped to $252 million, down 54 percent from $550 million a year ago, as the price of crude oil plunged. Seplat with dual listings in Lagos and London said revenues fell to $775 million during the period to December 31, against $880 million last year. The oil company proposed a total dividend of $0.15 per share for 2014, up from $0.10 in 2013.