Attainment Distribution Modeling

The comp plan cost depends not on one rep hitting quota, but on the distribution of attainment across the entire sales force. If you assume 100% average attainment and model costs on that basis, you will be wrong — because attainment is never evenly distributed. Typically, 20-30% of reps hit less than 60%, 40-50% hit between 60-120%, and 10-20% hit above 120%. The cost at each band is different because of base/variable splits and accelerators. Model the distribution, not the average.

Sales Team Cost Model — 20 AEs, $180K OTE:
──────────────────────────────────────────────────────
Band          Reps   Attain.   Revenue    Comp Cost
──────────────────────────────────────────────────────
0-50%           3      35%     $756K      $315K
50-80%          4      65%    $1,872K     $576K
80-100%         5      90%    $3,240K     $828K
100-120%        4     110%    $3,168K     $828K
120-150%        3     135%    $2,916K     $756K
150%+           1     180%    $1,296K     $306K
──────────────────────────────────────────────────────
Total:         20     ~91%   $13,248K    $3,609K

Avg attainment: 91% (not 100%)
Blended comp cost: 27.2% of revenue
Top 4 reps generate 33% of revenue
  at 24% of total comp cost.

Model the distribution. Not the average.

1. Use Historical Distribution Pull the last 8 quarters of attainment data and build a distribution curve. This is your baseline expectation for the next year. If you are growing the team, weight toward lower attainment (ramp effect). If the team is stable, the historical distribution is your best predictor.
2. Model Cost at Each Band Apply the actual comp plan math — base, variable, and accelerators — at each attainment band. Sum across the distribution to get total expected comp cost. This is always higher than the naive "average attainment x average comp" calculation because accelerators disproportionately increase cost at the high end.