In New York City, the rule of thumb is that a 15% drop in revenues is enough to make a restaurant shut permanently.

True: New York City restaurant industry sources (such as the NYC Hospitality Alliance, restaurant operators, industry analysts, or press reports quoting them) state a rule of thumb that about a 15% drop in revenue is enough to force a restaurant to close permanently, or something close to that (roughly 10–20%). Mostly true: such a rule of thumb is documented for restaurants in general, or with a somewhat different percentage, but is not specific to NYC. Mixed: sources report that restaurants' thin margins (often single digits) make modest falls in revenue fatal, but no recognised rule of thumb or threshold is stated. Mostly false: the only support is general statements about thin margins that the claim turns into a specific rule of thumb. False: industry sources indicate that restaurants typically survive revenue drops far larger than 15%, or that no such rule exists.

Set before the research began.

1. E1 How New York’s Restaurants Are Preparing for the Return of Indoor Dining Grub Street · 22 September 2020

   “Twenty-five percent capacity lets restaurants recoup some fraction of their pre-pandemic business but often not enough to break even, let alone come out ahead.”

2. E2 How New York’s Restaurants Are Preparing for the Return of Indoor Dining Grub Street · 22 September 2020

   “Grand Central Oyster Bar, according to Ingber, would need to be closer to 75 percent capacity to break even.”

3. E3 Will We Still Recognize New York City When It Reopens? Grub Street · 18 May 2020

   “It’s whittled down already-slim margins to practically nothing while giving commercial landlords new opportunities for power grabs.”

The evidence shows that NYC restaurant margins are slim and that reduced capacity often does not let restaurants break even [E1][E2][E3]. None of it states a 15% (or any) revenue-drop rule of thumb, or says that modest revenue falls cause closure. The absence of such a rule from these three articles does not show that no such rule exists.