What makes NYT bestseller ?

### Overview of New York Times Bestseller Criteria
The New York Times (NYT) Best Seller lists are compiled weekly by the NYT's Best Sellers Desk using a proprietary methodology that aggregates confidential sales data from thousands of diverse retailers across the United States, including national chains, independent bookstores, online vendors, supermarkets, and more. The lists reflect unit sales of books (print, e-book, graphic, and audiobook formats) reported for the previous week, weighted statistically to represent nationwide sales patterns.

Rankings prioritize individual consumer purchases after the book's official publication date, with bulk or institutional sales included only at the editors' discretion after vetting—they are flagged with a dagger (†) if counted. Certain categories like textbooks, perennial sellers, and free-trial audiobooks are excluded. The process is editorial, allowing for adjustments based on factors like sales distribution, regional spread, and suspected manipulation.

### Key Elements of the Criteria
- **Sales Tracking**: Based on actual transactions from a representative panel of vendors (e.g., over 4,000 bookstores and wholesalers by the early 2000s, covering tens of thousands of outlets). Data is adjusted to emphasize independent retailers.

- **Formats Included**: Print (hardcover, paperback), e-books (from major vendors like Amazon), graphic novels/manga (all formats), and audiobooks (physical/digital, excluding free trials). E-books and audiobooks are integrated into combined fiction/nonfiction lists.

- **Thresholds**: No fixed number is published, but estimates suggest 5,000–15,000 copies in a single week for most lists, with higher (10,000–20,000) for competitive categories like e-books. Sustained weekly sales (e.g., 5,000–10,000) help maintain rankings.

- **Exclusions and Vetting**: Bulk purchases (e.g., corporate giveaways) are scrutinized via audits and may be discounted or excluded if they appear manipulative (e.g., concentrated in one retailer or region). Sales must use standard identifiers like ISBN. Pre-publication sales count toward the first week.

- **List Categories**: Divided by genre (fiction/nonfiction), format (hardcover, paperback), and sublists (e.g., advice, children's, graphic books), each typically ranking 10–15 titles.

### Changes in Criteria Over the Past 20 Years (2005–2025)
The core methodology—proprietary sales aggregation with editorial discretion—has remained consistent, but there have been targeted updates to address emerging formats, manipulation, and list structure. No major overhauls occurred, but key evolutions include:

- **2011: Inclusion of E-Books**: The NYT began tracking e-book sales from leading online vendors, integrating them into combined fiction and nonfiction lists. This reflected the rise of digital reading but maintained the focus on diverse, non-exclusive vendors.
- **2017: Enhanced Anti-Manipulation Measures and List Restructuring**: In response to bulk-buy schemes (e.g., via firms like ResultSource), the NYT intensified curation, discounting concentrated bulk orders (e.g., multiple deliveries to one address) and emphasizing sales spread across regions/retailers. Nonfiction lists were shortened (e.g., General Nonfiction from 20 to 15 spots), favoring books with sustained sales over one-week spikes. Bulk inclusions became more rigorously vetted, with frequent exclusions for suspected gaming.
- **2019: List Expansions Without Core Changes**: The NYT revived the monthly mass-market paperback list (dropped in 2017) and added sublists for young adult and middle-grade books, but the underlying sales criteria stayed the same. This aimed to better reflect market segments without altering aggregation methods.

These adjustments have kept the lists influential while adapting to digital shifts and sales tactics, though the exact formula remains a trade secret to deter exploitation.