We're talking in the 2% range.
The reason for this was explained to me by my business partners after they heard me complain bitterly about all of the national level restrictions on large businesses and priorities given to small businesses.
There are many such disproportionate legal issues in Japan and it is very evident in a small town or a small neighborhood where the local stores sell national products at the top of their price range.
The reason for this long enduring high priority government support for small business, was an early recognition that small businesses hire the least qualified employees.
If there is a bell curve of employment suitability, it is small businesses that hire the workers on the bottom end of the curve.
In that case unreasonable support for small business is a rational employment policy.
If you doubt it, think of the hurdles required to get a job at a big corporation. Ordinary people just can't hack it.