{
  "url": "https://www.moonstonehq.com/articles/how-fast-psa-populations-grow",
  "slug": "how-fast-psa-populations-grow",
  "title": "How Fast Do PSA Populations Actually Grow?",
  "summary": "Watching 2,916 registries for a median 39 days, a quarter added nothing and the busiest 1% absorbed 29.87% of every new slab. The median grew 0.26% a week.",
  "section": "Data forensics",
  "published": "2026-09-22",
  "readMinutes": 10,
  "publisher": "moonstone",
  "findings": [
    {
      "value": "24.93%",
      "measures": "of 2,916 registries added nothing",
      "basis": "over a window of at least 28 days, median 39"
    },
    {
      "value": "29.87%",
      "measures": "of new slabs landed on the busiest 1%",
      "basis": "of 376,981 slabs added across the cohort"
    },
    {
      "value": "0.26%",
      "measures": "median weekly registry growth",
      "basis": "13 slabs for the median registry over its whole window"
    },
    {
      "value": "13",
      "measures": "slabs added by the median registry",
      "basis": "over its whole window, a median 39 days long"
    }
  ],
  "tables": [
    {
      "title": "The same question at six minimum window lengths",
      "columns": [
        "Minimum window",
        "Registries",
        "Median window observed",
        "Share that added nothing",
        "Slabs added",
        "Share taken by the busiest 1%"
      ],
      "rows": [
        {
          "Minimum window": "7 days",
          "Registries": "19,536",
          "Median window observed": "14 days",
          "Share that added nothing": "65.86%",
          "Slabs added": "587,817",
          "Share taken by the busiest 1%": "56.26%"
        },
        {
          "Minimum window": "14 days",
          "Registries": "15,674",
          "Median window observed": "14 days",
          "Share that added nothing": "59.92%",
          "Slabs added": "570,735",
          "Share taken by the busiest 1%": "52.34%"
        },
        {
          "Minimum window": "21 days",
          "Registries": "3,003",
          "Median window observed": "39 days",
          "Share that added nothing": "25.27%",
          "Slabs added": "387,272",
          "Share taken by the busiest 1%": "30.09%"
        },
        {
          "Minimum window": "28 days (headline)",
          "Registries": "2,916",
          "Median window observed": "39 days",
          "Share that added nothing": "24.93%",
          "Slabs added": "376,981",
          "Share taken by the busiest 1%": "29.87%"
        },
        {
          "Minimum window": "35 days",
          "Registries": "2,488",
          "Median window observed": "40 days",
          "Share that added nothing": "23.27%",
          "Slabs added": "332,735",
          "Share taken by the busiest 1%": "26.47%"
        },
        {
          "Minimum window": "42 days",
          "Registries": "1,177",
          "Median window observed": "45 days",
          "Share that added nothing": "5.86%",
          "Slabs added": "242,244",
          "Share taken by the busiest 1%": "16.26%"
        }
      ]
    },
    {
      "title": "Weekly registry growth, 2,916 registries watched a median 39 days",
      "columns": [
        "Percentile",
        "Weekly growth as a share of the opening registry"
      ],
      "rows": [
        {
          "Percentile": "25th",
          "Weekly growth as a share of the opening registry": "0.01%"
        },
        {
          "Percentile": "50th",
          "Weekly growth as a share of the opening registry": "0.26%"
        },
        {
          "Percentile": "75th",
          "Weekly growth as a share of the opening registry": "0.50%"
        },
        {
          "Percentile": "90th",
          "Weekly growth as a share of the opening registry": "0.86%"
        },
        {
          "Percentile": "95th",
          "Weekly growth as a share of the opening registry": "1.28%"
        },
        {
          "Percentile": "99th",
          "Weekly growth as a share of the opening registry": "6.31%"
        }
      ]
    },
    {
      "title": "Growth by registry size at the opening of the window",
      "columns": [
        "Opening registry",
        "Registries",
        "Share that added nothing",
        "Median slabs added",
        "Median weekly growth",
        "Slabs added"
      ],
      "rows": [
        {
          "Opening registry": "Under 500",
          "Registries": "1,247",
          "Share that added nothing": "50.68%",
          "Median slabs added": "0",
          "Median weekly growth": "0.00%",
          "Slabs added": "7,375"
        },
        {
          "Opening registry": "500 to 2,000",
          "Registries": "726",
          "Share that added nothing": "10.19%",
          "Median slabs added": "17",
          "Median weekly growth": "0.28%",
          "Slabs added": "26,445"
        },
        {
          "Opening registry": "2,000 to 10,000",
          "Registries": "672",
          "Share that added nothing": "2.83%",
          "Median slabs added": "77",
          "Median weekly growth": "0.33%",
          "Slabs added": "106,457"
        },
        {
          "Opening registry": "10,000 to 50,000",
          "Registries": "252",
          "Share that added nothing": "0.79%",
          "Median slabs added": "508",
          "Median weekly growth": "0.41%",
          "Slabs added": "186,314"
        },
        {
          "Opening registry": "50,000 and up",
          "Registries": "19",
          "Share that added nothing": "0.00%",
          "Median slabs added": "1,631",
          "Median weekly growth": "0.35%",
          "Slabs added": "50,390"
        }
      ]
    },
    {
      "title": "Growth by era, eras with 40 or more registries",
      "columns": [
        "Era",
        "Registries",
        "Share that added nothing",
        "Median weekly growth",
        "Slabs added"
      ],
      "rows": [
        {
          "Era": "Other",
          "Registries": "605",
          "Share that added nothing": "15.87%",
          "Median weekly growth": "0.46%",
          "Slabs added": "146,123"
        },
        {
          "Era": "Scarlet & Violet",
          "Registries": "563",
          "Share that added nothing": "17.94%",
          "Median weekly growth": "0.22%",
          "Slabs added": "72,347"
        },
        {
          "Era": "Mega",
          "Registries": "70",
          "Share that added nothing": "25.71%",
          "Median weekly growth": "1.28%",
          "Slabs added": "70,672"
        },
        {
          "Era": "Sword & Shield",
          "Registries": "458",
          "Share that added nothing": "29.91%",
          "Median weekly growth": "0.16%",
          "Slabs added": "39,980"
        },
        {
          "Era": "WotC",
          "Registries": "410",
          "Share that added nothing": "17.56%",
          "Median weekly growth": "0.26%",
          "Slabs added": "21,038"
        },
        {
          "Era": "Sun & Moon",
          "Registries": "178",
          "Share that added nothing": "23.03%",
          "Median weekly growth": "0.21%",
          "Slabs added": "9,201"
        },
        {
          "Era": "XY",
          "Registries": "132",
          "Share that added nothing": "31.82%",
          "Median weekly growth": "0.23%",
          "Slabs added": "5,401"
        },
        {
          "Era": "EX",
          "Registries": "229",
          "Share that added nothing": "51.53%",
          "Median weekly growth": "0.00%",
          "Slabs added": "3,219"
        },
        {
          "Era": "Diamond & Pearl",
          "Registries": "119",
          "Share that added nothing": "36.97%",
          "Median weekly growth": "0.27%",
          "Slabs added": "1,231"
        },
        {
          "Era": "Black & White",
          "Registries": "98",
          "Share that added nothing": "40.82%",
          "Median weekly growth": "0.23%",
          "Slabs added": "916"
        },
        {
          "Era": "HeartGold SoulSilver",
          "Registries": "41",
          "Share that added nothing": "41.46%",
          "Median weekly growth": "0.24%",
          "Slabs added": "472"
        }
      ]
    },
    {
      "title": "The largest absolute adds in the cohort",
      "columns": [
        "Card",
        "Set",
        "Slabs added",
        "Days watched",
        "Registry, open to close",
        "Weekly growth"
      ],
      "rows": [
        {
          "Card": "[Mega Charizard X ex](/card/mep-023)",
          "Set": "MEP Black Star Promos",
          "Slabs added": "9,033",
          "Days watched": "32",
          "Registry, open to close": "101,415 to 110,448",
          "Weekly growth": "1.95%"
        },
        {
          "Card": "[コダック](/card/ja-M2a-199)",
          "Set": "MEGA Dream ex",
          "Slabs added": "8,794",
          "Days watched": "40",
          "Registry, open to close": "27,559 to 36,353",
          "Weekly growth": "5.58%"
        },
        {
          "Card": "[メガゲンガーex](/card/ja-M2a-240)",
          "Set": "MEGA Dream ex",
          "Slabs added": "8,056",
          "Days watched": "41",
          "Registry, open to close": "36,007 to 44,063",
          "Weekly growth": "3.82%"
        },
        {
          "Card": "[Pikachu](/card/jat-649586)",
          "Set": "M-P Promotional Cards",
          "Slabs added": "7,565",
          "Days watched": "31",
          "Registry, open to close": "324,788 to 332,353",
          "Weekly growth": "0.53%"
        },
        {
          "Card": "[Mega Gengar ex](/card/me02.5-269)",
          "Set": "[Ascended Heroes](/set/ascended%20heroes)",
          "Slabs added": "6,328",
          "Days watched": "36",
          "Registry, open to close": "14,648 to 20,976",
          "Weekly growth": "8.40%"
        },
        {
          "Card": "[メガカイリューex](/card/ja-M2a-246)",
          "Set": "MEGA Dream ex",
          "Slabs added": "6,158",
          "Days watched": "37",
          "Registry, open to close": "27,216 to 33,374",
          "Weekly growth": "4.28%"
        },
        {
          "Card": "[Mega Charizard X ex](/card/jat-655886)",
          "Set": "M2: Inferno X",
          "Slabs added": "4,859",
          "Days watched": "42",
          "Registry, open to close": "55,520 to 60,379",
          "Weekly growth": "1.46%"
        },
        {
          "Card": "[Clefairy](/card/me03-094)",
          "Set": "[Perfect Order](/set/perfect%20order)",
          "Slabs added": "4,607",
          "Days watched": "46",
          "Registry, open to close": "4,176 to 8,783",
          "Weekly growth": "16.79%"
        },
        {
          "Card": "[ブラッキーex](/card/ja-SV8a-217)",
          "Set": "Terastal Festival ex",
          "Slabs added": "4,480",
          "Days watched": "49",
          "Registry, open to close": "89,272 to 93,752",
          "Weekly growth": "0.72%"
        }
      ]
    },
    {
      "title": "PSA 10 premium by registry growth tercile, 1,228 cards opening above 500 slabs",
      "columns": [
        "Growth tercile",
        "Cards",
        "Median weekly growth",
        "Median PSA 10 premium"
      ],
      "rows": [
        {
          "Growth tercile": "Slowest third",
          "Cards": "409",
          "Median weekly growth": "0.13%",
          "Median PSA 10 premium": "9.57x"
        },
        {
          "Growth tercile": "Middle third",
          "Cards": "410",
          "Median weekly growth": "0.32%",
          "Median PSA 10 premium": "8.78x"
        },
        {
          "Growth tercile": "Fastest third",
          "Cards": "409",
          "Median weekly growth": "0.67%",
          "Median PSA 10 premium": "7.05x"
        }
      ]
    }
  ],
  "charts": [],
  "sections": [
    "The answer depends on how long you watch",
    "What the median registry does",
    "Where the graders are actually pointed",
    "Does the flow cost the premium?",
    "What this study cannot show",
    "What would overturn this"
  ],
  "method": [
    "Source: `population_snapshots`, our own daily recording of the PSA registry line served for each tracked product, read through September 22, 2026. Each registry's series is passed through the house continuity rule, which cuts the series at any reading that contradicts population physics, a total that fell or a step that multiplied it threefold, because those are provider remaps onto a different registry line and not a week of grading; only the segment since the last cut is measured, and a line whose identity just changed with a single reading behind it is withheld entirely. Keys flagged by the shared-line rule, where two products return the same registry line, are dropped. Rows are collapsed to one per registry key. The headline cohort is every surviving registry whose publishable segment spans at least 28 days with at least two readings and a positive opening total, which is 2,916 registries with a median observed span of 39 days and a maximum of 51. Growth is closing total minus opening total, expressed per week as (added / days) x 7 and as a percentage of the opening total. The article publishes the same measurements at five other minimum windows so the reader can see how much the window choice is doing. The price join uses the latest `price_history` ask and the latest PSA 10 `graded_snapshots` sold median on ten or more verified comps, collapsed to one row per product id, and additionally requires an opening registry of 500 slabs or more, because a weekly growth rate computed on an opening total of forty is a statement about the forty; the article prints the result without that floor as well. Raw figures are asks, graded figures are sold medians. Not financial advice."
  ],
  "terms": "Figures are moonstone's own recorded measurements, dated as published. Quote them with the population stated beside them. The article at `url` is the human form of this file."
}