Refactor the benchmarks again
Refactor the benchmarks again

Results:

benchmarking boxed/1000/builder
time                 59.84 μs   (59.29 μs .. 60.50 μs)
                     0.998 R²   (0.997 R² .. 1.000 R²)
mean                 60.16 μs   (59.62 μs .. 60.95 μs)
std dev              2.558 μs   (1.487 μs .. 3.415 μs)
variance introduced by outliers: 46% (moderately inflated)

benchmarking boxed/1000/growing
time                 209.8 μs   (208.9 μs .. 210.6 μs)
                     1.000 R²   (1.000 R² .. 1.000 R²)
mean                 209.6 μs   (209.1 μs .. 210.1 μs)
std dev              1.944 μs   (1.526 μs .. 2.459 μs)

benchmarking boxed/10000/builder
time                 1.907 ms   (1.895 ms .. 1.921 ms)
                     1.000 R²   (0.999 R² .. 1.000 R²)
mean                 1.895 ms   (1.884 ms .. 1.907 ms)
std dev              41.68 μs   (33.66 μs .. 49.92 μs)

benchmarking boxed/10000/growing
time                 2.700 ms   (2.597 ms .. 2.792 ms)
                     0.992 R²   (0.989 R² .. 0.996 R²)
mean                 2.606 ms   (2.568 ms .. 2.652 ms)
std dev              138.9 μs   (109.3 μs .. 165.8 μs)
variance introduced by outliers: 35% (moderately inflated)

benchmarking boxed/100000/builder
time                 32.05 ms   (31.25 ms .. 32.85 ms)
                     0.998 R²   (0.996 R² .. 0.999 R²)
mean                 32.78 ms   (32.09 ms .. 33.95 ms)
std dev              2.099 ms   (726.2 μs .. 3.406 ms)
variance introduced by outliers: 22% (moderately inflated)

benchmarking boxed/100000/growing
time                 30.39 ms   (28.95 ms .. 31.87 ms)
                     0.995 R²   (0.991 R² .. 0.998 R²)
mean                 29.82 ms   (29.16 ms .. 30.65 ms)
std dev              1.470 ms   (852.1 μs .. 1.832 ms)
variance introduced by outliers: 16% (moderately inflated)

benchmarking boxed/1000000/builder
time                 359.6 ms   (261.1 ms .. 426.5 ms)
                     0.992 R²   (0.972 R² .. 1.000 R²)
mean                 356.3 ms   (335.9 ms .. 366.6 ms)
std dev              17.63 ms   (67.99 as .. 17.83 ms)
variance introduced by outliers: 19% (moderately inflated)

benchmarking boxed/1000000/growing
time                 304.4 ms   (291.2 ms .. 319.0 ms)
                     0.999 R²   (0.997 R² .. 1.000 R²)
mean                 293.8 ms   (288.8 ms .. 297.6 ms)
std dev              5.068 ms   (2.172 ms .. 6.338 ms)
variance introduced by outliers: 16% (moderately inflated)

benchmarking boxed/10000000/builder
time                 3.693 s    (3.108 s .. 4.281 s)
                     0.997 R²   (0.988 R² .. 1.000 R²)
mean                 3.945 s    (3.791 s .. 4.059 s)
std dev              173.0 ms   (0.0 s .. 197.2 ms)
variance introduced by outliers: 19% (moderately inflated)

benchmarking boxed/10000000/growing
time                 3.515 s    (3.139 s .. 3.812 s)
                     0.999 R²   (0.995 R² .. 1.000 R²)
mean                 3.437 s    (3.370 s .. 3.476 s)
std dev              60.32 ms   (0.0 s .. 66.73 ms)
variance introduced by outliers: 19% (moderately inflated)

benchmarking unboxed/1000/builder
time                 59.20 μs   (57.66 μs .. 60.87 μs)
                     0.996 R²   (0.995 R² .. 0.999 R²)
mean                 59.64 μs   (58.84 μs .. 60.88 μs)
std dev              2.944 μs   (2.280 μs .. 3.745 μs)
variance introduced by outliers: 54% (severely inflated)

benchmarking unboxed/1000/growing
time                 197.5 μs   (195.9 μs .. 199.6 μs)
                     0.999 R²   (0.999 R² .. 1.000 R²)
mean                 197.8 μs   (196.2 μs .. 199.8 μs)
std dev              5.576 μs   (4.635 μs .. 6.943 μs)
variance introduced by outliers: 23% (moderately inflated)

benchmarking unboxed/10000/builder
time                 1.697 ms   (1.672 ms .. 1.722 ms)
                     0.999 R²   (0.998 R² .. 0.999 R²)
mean                 1.709 ms   (1.694 ms .. 1.720 ms)
std dev              42.34 μs   (33.00 μs .. 53.54 μs)
variance introduced by outliers: 13% (moderately inflated)

benchmarking unboxed/10000/growing
time                 2.244 ms   (2.200 ms .. 2.297 ms)
                     0.998 R²   (0.997 R² .. 1.000 R²)
mean                 2.217 ms   (2.207 ms .. 2.231 ms)
std dev              43.72 μs   (33.02 μs .. 64.60 μs)

benchmarking unboxed/100000/builder
time                 30.00 ms   (29.28 ms .. 30.65 ms)
                     0.998 R²   (0.995 R² .. 0.999 R²)
mean                 30.34 ms   (29.81 ms .. 31.07 ms)
std dev              1.568 ms   (787.1 μs .. 2.360 ms)
variance introduced by outliers: 17% (moderately inflated)

benchmarking unboxed/100000/growing
time                 23.12 ms   (22.74 ms .. 23.88 ms)
                     0.996 R²   (0.990 R² .. 1.000 R²)
mean                 23.44 ms   (23.07 ms .. 23.86 ms)
std dev              859.0 μs   (597.7 μs .. 1.101 ms)

benchmarking unboxed/1000000/builder
time                 280.6 ms   (271.3 ms .. 287.9 ms)
                     1.000 R²   (0.998 R² .. 1.000 R²)
mean                 316.7 ms   (306.6 ms .. 334.9 ms)
std dev              17.44 ms   (2.560 ms .. 22.38 ms)
variance introduced by outliers: 16% (moderately inflated)

benchmarking unboxed/1000000/growing
time                 222.9 ms   (215.0 ms .. 228.4 ms)
                     0.999 R²   (0.995 R² .. 1.000 R²)
mean                 223.1 ms   (219.5 ms .. 225.3 ms)
std dev              3.460 ms   (1.354 ms .. 4.725 ms)
variance introduced by outliers: 14% (moderately inflated)

benchmarking unboxed/10000000/builder
time                 2.975 s    (2.485 s .. 3.566 s)
                     0.995 R²   (0.984 R² .. 1.000 R²)
mean                 3.251 s    (3.109 s .. 3.355 s)
std dev              157.7 ms   (0.0 s .. 180.0 ms)
variance introduced by outliers: 19% (moderately inflated)

benchmarking unboxed/10000000/growing
time                 2.280 s    (2.047 s .. 2.483 s)
                     0.999 R²   (0.995 R² .. 1.000 R²)
mean                 2.210 s    (2.164 s .. 2.237 s)
std dev              41.37 ms   (0.0 s .. 46.09 ms)
variance introduced by outliers: 19% (moderately inflated)

nikita-volkov/vector-builder