OptionalrateSignificant projects that were excluded from the aggregate because at least
one phase surfaced reason === "rate_limit". Empty when no project was
rate-limited. Optional for backward compatibility with previously
serialized benchmark data.
Mean score across significant projects that finished without hitting a rate-limit. Rate-limited projects are excluded from both the numerator and the denominator (see rateLimited). When every significant project was rate-limited, this is
0.