Correction: people with an autism diagnosis. You are much more likely to get a diagnosis if you are in contact with the psychiatric healthcare system (e.g. if you are suicidal)

Any statistics done on the subset of autistic people with a diagnosis would therefore be skewed towards the mean of the subset of the general population who are in contact with the psychiatric system

There's a huge number of undiagnosed - estimates range between 90%-98% of people who would fit the criteria for ASD remain undiagnosed. These people remain undiagnosed because they generally live normal lives with jobs, wives, husbands, children, pets, and so on, which provides a support system to help them with the challenges they face

The group of undiagnosed autistic people are however much more likely to be underemployed, i.e. they employed in a much lower position than their education and experience would generally suggest. This is due to the systemic issues they face caused by a lack of accommodations which naturally increases the risk of them having a mental health crisis that puts them in contact with the psychiatric system

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