Sharply higher crude oil prices in the first half of 2008 and crumbling North American end-user demand have led to substantial weakness among downstream companies' second-quarter results. Significant year-on-year decreases in operating results were seen at bellwether Valero (second-quarter [2Q] net income [NI] of $734 million versus $2.25 billion in 2007, a 67% drop), Tesoro (2Q NI of $4 million versus $443 million in 2007, a 99% drop), Marathon (segment NI of $158 million versus $1.25 billion in 2007, an 87% drop), ExxonMobil (segment NI of $1.56 billion versus $3.39 billion in 2007, a 54% drop), and Chevron (a segment loss of $734 million versus $1.3 billion gain in 2007).