You know that 32 degrees Fahrenheit is equivalent to 0 degrees Celsius, and that 212 degrees Fahrenheit is equivalent to 100 degrees Celsius. Use the trend curve to determine the relationship between Fahrenheit and Celsius temperatures. When you create your initial chart, before clicking Finish, you must indicate (using Switch Rows and Columns from the Design Tab on Chart Tools) that data is in columns and not rows because with only two data points, Excel assumes different variables are in different rows.