Email List Growth Forecast Calculator

Key outcomes

• – net adds (total)
• – avg net adds / month
• – months to reach goal

Assumptions

Formulas used

• New[t] = round(A_base × season[t]) + boost[t]
• Churn[t] = round(S[t−1] × churn%)
• Hygiene[t] = 0.5% at months 3,6,9,12… (if on)
• S[t] = max(0, S[t−1] + New[t] − Churn[t] − Hygiene[t])
• Goal time = min t where S[t] ≥ Goal

Growth over time

What moves the needle