There are no accurate figures because this effect is still being studied and is not completely understood yet.
It is suggested that the majority of the population on Earth experience ASMR, most of us probably don't even realise it.
ASMR reduces stress in the same was a meditation or a massage. Tingles in the brain caused by ASMR will psychologically massage the brain and feel good. This is what causes relaxation and reduction in stress.
ASMR affects a large chunk of the population. However there are some people who reportedly do not experience the effects of ASMR. We still don't completely understand it and are still investigating it.
ASMR causes the feelings of relaxation and brain tingling. The brain tingling psychologically massages the brain, giving the same effect as a physical back massage or meditation. When a person becomes relaxed, their breathing slows and their heartbeat slows.
ASMR is known to cause several feelings in the body. The common ones are brain tingling, relaxation, calmness and sleepiness.
This is an opinion that differs by individual.
Some people enjoy ASMR as a relaxation technique. Other people are not affected by it at all.