Normal respiratory rate for an adult at rest is about 10-12 breaths in one minute. The respiratory rate is measured as a number of inhalations or exhalations per one minute, and it is usually done at rest. People with chronic diseases, when they have mild forms of heart disease, asthma, diabetes, cancer and many other conditions breathe little bit faster, about 15-20 breaths per minute. During last stages of diseases, when people are severely sick or they are terminally ill, the respiratory rate is much greate bout 30-40 breaths per minute. There are many studies that relate to, for example, cancer, cystic fibrosis, HIV, and many other conditions. Normal respiratory rate in children is higher, and here is a table that provides typical numbers depending on the age of a child. The ideal respiratory rate is only about 3,4,5 breaths per minute and, when a person has this respiratory rate, of course, we are again talking about automatic or unconscious breathing pattern, like when a person is not aware about his or her breathing. or breathing during sleep, because during sleep generally the respiratory rate is nearly the same as people have at rest. The ideal respiratory rate that provides maximum body oxygen content. And in order to have more oxygen, breathing should be slow and lighter. And, therefore, the ideal respiratory rate is only about 3-5 breaths per minute. On this diagram you can see different breathing patterns and corresponding results for the body oxygen test. So there are ideal breathing pattern; normal breathing pattern, which we can find in medical textbooks; the breathing pattern, which is common among sick people; and finally there is a breathing pattern, which corresponds to vast majority of severely sick people. When people breathe very fast, body oxygen content is very low, and that, of course, is a key factor that promotes or advances chronic diseases. If we think about various other conditions, the respiratory rate, of course, can vary a lot. For example, during pranayama breathing exercise, even ordinary people can start doing pranayama with only 2-3 breaths per minute. You take deep inhalation, hold breath, slowly-slowly exhale (this is how pranayama should be practiced), then We again hold breath... But yoga maasters, if they practice pranayama maybe for some years even, are able to do the same exercise with only 0.5 breath in one minute. That means they take one breath in 2 minutes time. And that of course indicate that their breathing at rest is already very-very slow, and its not so difficult for them to practice pranayama with a such very slow breathing rate. At the same time, there is an opposite exercise, which is called fire breath (bhastrika), like when person tries to breathe very-very fast, but with very small tidal volum nly about maybe 200 ml so that he gets more CO2, and that provides more oxygen for body cells. During this exercise of yoga, hatha yoga, fire breath, the respiratory rate can be about 100-120 breaths per minute. And if we think about physical exercise with rate, breathing rate or respiratory rate is also higher. It's common for many people to breathe about 50-60 breaths in one minute, but since we generate CO2, oxygen transport is, in fact, can be improved, especially if we breathe only through the nose, during physical exercise. When people practice breathing retraining, the respiratory rate gradually becomes slower, and that is also an additional factor that indicates improved body oxygenation. You can find more details about respiratory rate in relation to the body oxygen test, and other parameters, for example, CO2 in the alveoli, minute ventilation, heart rate (average numbers) in the Buteyko table of health zones and on the web pages of NormalBreathing.com