I want to start newsletter but analyze: how many subscribers needed to make money? Map newsletter economics: free vs. paid conversion rates, pricing tiers. Calculate: if 5-10% convert to paid, need this many free subscribers for income. Show me the newsletter math: this many subscribers, this conversion, this income. Give me the newsletter strategy: grow free list to this size, then monetize. Include: how many subscribers needed for newsletter income, what conversion rates are realistic, and how long to build subscriber base.