NEW YORK (AP) â¿¿ Chevron Corp. posted a 41 percent gain in net income for the fourth quarter as the company produced more oil and gas, improved the performance of its refinery business and realized a gain from swapping assets in an Australian natural gas field.Chevron Corp. posted net income of $7.2 billion for the quarter on revenue of $60.6 billion. That's up from $5.1 billion on revenue of $60 billion a year ago. On a per-share basis, Chevron earned $3.70. Analysts expected the company to earn $3.06 per share, according to FactSet. ___ Generic competition, charges cut Merck Q4 profit Merck & Co.'s fourth-quarter profit fell 7 percent because of hits from generic competition and one-time charges, and the company pushed back plans for seeking approval of a key experimental osteoporosis drug. The quarterly results beat Wall Street expectations, but Merck shares fell Friday as investors learned the company is reviewing safety and efficacy data from a crucial late-stage patient test of the osteoporosis drug odanacatib. During a conference call with analysts, Merck executives said that instead of applying for approval of odanacatib in the first half of this year, the company won't do that until 2014. That will allow Merck time to finish an extension of a study that includes about 8,200 women, so it can submit those longer-term results to regulators â¿¿ apparently a strategy to improve chances the drug will be approved. ___ Mattel 4Q results miss Wall Street's expectations NEW YORK (AP) â¿¿ It was a blue Christmas in toyland. Weak demand over the holidays for toys like Barbie and Matchbox led Mattel's results to fall short of expectations in the key holiday quarter. A litigation charge also weighed on results and net income fell 17 percent. Still the results from the world's largest toymaker came in stronger than the overall toy industry, and company executives vowed to do better in 2013. The fourth quarter is key because toy makers can make up to 40 percent of annual sales during the period.