diff --git a/build.js b/build.js
index c8859dc..a37a930 100644
--- a/build.js
+++ b/build.js
@@ -83,7 +83,7 @@ function onconcat(body) {
         code: script.code,
         name: script.english,
         numeric: script.numeric,
-        pva: script.pva || null,
+        pva: script.pva || undefined,
         date: script.date
       }
     })
diff --git a/index.json b/index.json
index d300fb3..413302e 100644
--- a/index.json
+++ b/index.json
@@ -10,7 +10,6 @@
     "code": "Afak",
     "name": "Afaka",
     "numeric": "439",
-    "pva": null,
     "date": "2010-12-21"
   },
   {
@@ -38,7 +37,6 @@
     "code": "Aran",
     "name": "Arabic (Nastaliq variant)",
     "numeric": "161",
-    "pva": null,
     "date": "2014-11-15"
   },
   {
@@ -108,7 +106,6 @@
     "code": "Blis",
     "name": "Blissymbols",
     "numeric": "550",
-    "pva": null,
     "date": "2004-05-01"
   },
   {
@@ -192,7 +189,6 @@
     "code": "Cirt",
     "name": "Cirth",
     "numeric": "291",
-    "pva": null,
     "date": "2004-05-01"
   },
   {
@@ -206,7 +202,6 @@
     "code": "Cpmn",
     "name": "Cypro-Minoan",
     "numeric": "402",
-    "pva": null,
     "date": "2017-07-26"
   },
   {
@@ -227,7 +222,6 @@
     "code": "Cyrs",
     "name": "Cyrillic (Old Church Slavonic variant)",
     "numeric": "221",
-    "pva": null,
     "date": "2004-05-01"
   },
   {
@@ -269,14 +263,12 @@
     "code": "Egyd",
     "name": "Egyptian demotic",
     "numeric": "070",
-    "pva": null,
     "date": "2004-05-01"
   },
   {
     "code": "Egyh",
     "name": "Egyptian hieratic",
     "numeric": "060",
-    "pva": null,
     "date": "2004-05-01"
   },
   {
@@ -381,7 +373,6 @@
     "code": "Hanb",
     "name": "Han with Bopomofo (alias for Han + Bopomofo)",
     "numeric": "503",
-    "pva": null,
     "date": "2016-01-19"
   },
   {
@@ -409,14 +400,12 @@
     "code": "Hans",
     "name": "Han (Simplified variant)",
     "numeric": "501",
-    "pva": null,
     "date": "2004-05-29"
   },
   {
     "code": "Hant",
     "name": "Han (Traditional variant)",
     "numeric": "502",
-    "pva": null,
     "date": "2004-05-29"
   },
   {
@@ -479,7 +468,6 @@
     "code": "Inds",
     "name": "Indus (Harappan)",
     "numeric": "610",
-    "pva": null,
     "date": "2004-05-01"
   },
   {
@@ -493,7 +481,6 @@
     "code": "Jamo",
     "name": "Jamo (alias for Jamo subset of Hangul)",
     "numeric": "284",
-    "pva": null,
     "date": "2016-01-19"
   },
   {
@@ -507,14 +494,12 @@
     "code": "Jpan",
     "name": "Japanese (alias for Han + Hiragana + Katakana)",
     "numeric": "413",
-    "pva": null,
     "date": "2006-06-21"
   },
   {
     "code": "Jurc",
     "name": "Jurchen",
     "numeric": "510",
-    "pva": null,
     "date": "2010-12-21"
   },
   {
@@ -556,7 +541,6 @@
     "code": "Kitl",
     "name": "Khitan large script",
     "numeric": "505",
-    "pva": null,
     "date": "2015-07-15"
   },
   {
@@ -577,14 +561,12 @@
     "code": "Kore",
     "name": "Korean (alias for Hangul + Han)",
     "numeric": "287",
-    "pva": null,
     "date": "2007-06-13"
   },
   {
     "code": "Kpel",
     "name": "Kpelle",
     "numeric": "436",
-    "pva": null,
     "date": "2010-03-26"
   },
   {
@@ -612,14 +594,12 @@
     "code": "Latf",
     "name": "Latin (Fraktur variant)",
     "numeric": "217",
-    "pva": null,
     "date": "2004-05-01"
   },
   {
     "code": "Latg",
     "name": "Latin (Gaelic variant)",
     "numeric": "216",
-    "pva": null,
     "date": "2004-05-01"
   },
   {
@@ -633,7 +613,6 @@
     "code": "Leke",
     "name": "Leke",
     "numeric": "364",
-    "pva": null,
     "date": "2015-07-07"
   },
   {
@@ -675,7 +654,6 @@
     "code": "Loma",
     "name": "Loma",
     "numeric": "437",
-    "pva": null,
     "date": "2010-03-26"
   },
   {
@@ -731,7 +709,6 @@
     "code": "Maya",
     "name": "Mayan hieroglyphs",
     "numeric": "090",
-    "pva": null,
     "date": "2004-05-01"
   },
   {
@@ -787,7 +764,6 @@
     "code": "Moon",
     "name": "Moon (Moon code, Moon script, Moon type)",
     "numeric": "218",
-    "pva": null,
     "date": "2006-12-11"
   },
   {
@@ -850,14 +826,12 @@
     "code": "Nkdb",
     "name": "Naxi Dongba (na²¹ɕi³³ to³³ba²¹, Nakhi Tomba)",
     "numeric": "085",
-    "pva": null,
     "date": "2017-07-26"
   },
   {
     "code": "Nkgb",
     "name": "Naxi Geba (na²¹ɕi³³ gʌ²¹ba²¹, 'Na-'Khi ²Ggŏ-¹baw, Nakhi Geba)",
     "numeric": "420",
-    "pva": null,
     "date": "2017-07-26"
   },
   {
@@ -962,7 +936,6 @@
     "code": "Phlv",
     "name": "Book Pahlavi",
     "numeric": "133",
-    "pva": null,
     "date": "2007-07-15"
   },
   {
@@ -983,7 +956,6 @@
     "code": "Piqd",
     "name": "Klingon (KLI pIqaD)",
     "numeric": "293",
-    "pva": null,
     "date": "2015-12-16"
   },
   {
@@ -997,14 +969,12 @@
     "code": "Qaaa",
     "name": "Reserved for private use (start)",
     "numeric": "900",
-    "pva": null,
     "date": "2004-05-29"
   },
   {
     "code": "Qabx",
     "name": "Reserved for private use (end)",
     "numeric": "949",
-    "pva": null,
     "date": "2004-05-29"
   },
   {
@@ -1025,7 +995,6 @@
     "code": "Roro",
     "name": "Rongorongo",
     "numeric": "620",
-    "pva": null,
     "date": "2004-05-01"
   },
   {
@@ -1046,7 +1015,6 @@
     "code": "Sara",
     "name": "Sarati",
     "numeric": "292",
-    "pva": null,
     "date": "2004-05-29"
   },
   {
@@ -1088,7 +1056,6 @@
     "code": "Shui",
     "name": "Shuishu",
     "numeric": "530",
-    "pva": null,
     "date": "2017-07-26"
   },
   {
@@ -1165,21 +1132,18 @@
     "code": "Syre",
     "name": "Syriac (Estrangelo variant)",
     "numeric": "138",
-    "pva": null,
     "date": "2004-05-01"
   },
   {
     "code": "Syrj",
     "name": "Syriac (Western variant)",
     "numeric": "137",
-    "pva": null,
     "date": "2004-05-01"
   },
   {
     "code": "Syrn",
     "name": "Syriac (Eastern variant)",
     "numeric": "136",
-    "pva": null,
     "date": "2004-05-01"
   },
   {
@@ -1242,7 +1206,6 @@
     "code": "Teng",
     "name": "Tengwar",
     "numeric": "290",
-    "pva": null,
     "date": "2004-05-01"
   },
   {
@@ -1305,7 +1268,6 @@
     "code": "Visp",
     "name": "Visible Speech",
     "numeric": "280",
-    "pva": null,
     "date": "2004-05-01"
   },
   {
@@ -1326,7 +1288,6 @@
     "code": "Wole",
     "name": "Woleai",
     "numeric": "480",
-    "pva": null,
     "date": "2010-12-21"
   },
   {
@@ -1375,28 +1336,24 @@
     "code": "Zmth",
     "name": "Mathematical notation",
     "numeric": "995",
-    "pva": null,
     "date": "2007-11-26"
   },
   {
     "code": "Zsye",
     "name": "Symbols (Emoji variant)",
     "numeric": "993",
-    "pva": null,
     "date": "2015-12-16"
   },
   {
     "code": "Zsym",
     "name": "Symbols",
     "numeric": "996",
-    "pva": null,
     "date": "2007-11-26"
   },
   {
     "code": "Zxxx",
     "name": "Code for unwritten documents",
     "numeric": "997",
-    "pva": null,
     "date": "2011-06-21"
   },
   {