The Birch (Employee Growth) Index is an economic indicator of employment.
It multiplies absolute job growth by relative job growth, which reveals the employment-creation power of differently sized enterprises.
It was devised by economist David L. Birch at the Massachusetts Institute of Technology.
In 1980 Birch published an influential study that showed 70% of job growth in the U.S. came from enterprises with fewer than 100 employees.
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