No single core temperature can be considered normal because measurements in many healthy people have shown a range of normal temperatures measured orally, as shown in Figure 74-1, from less than 97°F (36°C) to greater than 99.5°F (37.5°C). The average normal core temperature is generally considered to be between 98.0°F and 98.6°F when measured orally and about 1°F higher when measured rectally.