assertThrows(IllegalStateException.class, EMPTY_STATS_ITERABLE::mean);
    assertThat(ONE_VALUE_STATS.mean()).isWithin(ALLOWED_ERROR).of(ONE_VALUE);
    assertThat(Stats.of(POSITIVE_INFINITY).mean()).isPositiveInfinity();
    assertThat(Stats.of(NEGATIVE_INFINITY).mean()).isNegativeInfinity();
    assertThat(Stats.of(NaN).mean()).isNaN();
    assertThat(TWO_VALUES_STATS.mean()).isWithin(ALLOWED_ERROR).of(TWO_VALUES_MEAN);