The average price of a gallon of gas in 2013 dropped $0.12 (3 percent) from $3.61 in 2012 (to $3.49 in 2013) Required: 1. Conduct a horizontal analysis by calculating the year-over-year changes in each line item, expressed in dollars and in percentages for the income statement of Chevron Corporation for the year ended December 31, 2013 (amounts in billions). (Decreases should be indicated by a minus sign. Enter your answers in billions (i.e., 10,000,000,000 should be entered as 10). Round your percentage answers to 1 decimal place.) CHEVRON CORPORATION Income Statements (dollars in billions) For the Year Ended December 31 Change in 2013 2012 Dollars Percentage Total Revenues Costs of Crude Oil and Products S 270 289 127 51 121 46 S 56 S 65