diff --git a/schema.json b/schema.json
index 8f23f5c9..b322019d 100644
--- a/schema.json
+++ b/schema.json
@@ -309,31 +309,31 @@
         "high": {
           "type": "array",
           "items": {
-            "yahooFinanceType": "number"
+            "yahooFinanceType": "number|null"
           }
         },
         "low": {
           "type": "array",
           "items": {
-            "yahooFinanceType": "number"
+            "yahooFinanceType": "number|null"
           }
         },
         "open": {
           "type": "array",
           "items": {
-            "yahooFinanceType": "number"
+            "yahooFinanceType": "number|null"
           }
         },
         "close": {
           "type": "array",
           "items": {
-            "yahooFinanceType": "number"
+            "yahooFinanceType": "number|null"
           }
         },
         "volume": {
           "type": "array",
           "items": {
-            "yahooFinanceType": "number"
+            "yahooFinanceType": "number|null"
           }
         }
       },
@@ -351,7 +351,7 @@
         "adjclose": {
           "type": "array",
           "items": {
-            "yahooFinanceType": "number"
+            "yahooFinanceType": "number|null"
           }
         }
       }
@@ -402,22 +402,22 @@
           "yahooFinanceType": "date"
         },
         "high": {
-          "yahooFinanceType": "number"
+          "yahooFinanceType": "number|null"
         },
         "low": {
-          "yahooFinanceType": "number"
+          "yahooFinanceType": "number|null"
         },
         "open": {
-          "yahooFinanceType": "number"
+          "yahooFinanceType": "number|null"
         },
         "close": {
-          "yahooFinanceType": "number"
+          "yahooFinanceType": "number|null"
         },
         "volume": {
-          "yahooFinanceType": "number"
+          "yahooFinanceType": "number|null"
         },
         "adjclose": {
-          "yahooFinanceType": "number"
+          "yahooFinanceType": "number|null"
         }
       },
       "required": [
diff --git a/tests/http/chart-WSU.DE-2023-08-04-to-2023-08-09.json b/tests/http/chart-WSU.DE-2023-08-04-to-2023-08-09.json
new file mode 100644
index 00000000..4a57988b
--- /dev/null
+++ b/tests/http/chart-WSU.DE-2023-08-04-to-2023-08-09.json
@@ -0,0 +1,70 @@
+{
+  "request": {
+    "url": "https://query2.finance.yahoo.com/v8/finance/chart/WSU.DE?useYfid=true&interval=1d&includePrePost=true&events=div%7Csplit%7Cearn&lang=en-US&period1=1691107200&period2=1691539200"
+  },
+  "response": {
+    "ok": true,
+    "status": 200,
+    "statusText": "OK",
+    "headers": {
+      "content-type": [
+        "application/json;charset=utf-8"
+      ],
+      "cache-control": [
+        "public, max-age=10, stale-while-revalidate=20"
+      ],
+      "vary": [
+        "Origin,Accept-Encoding"
+      ],
+      "y-rid": [
+        "0psfdllifb6ns"
+      ],
+      "x-yahoo-request-id": [
+        "0psfdllifb6ns"
+      ],
+      "x-request-id": [
+        "dad202de-8136-4ccf-ae1d-d875be3a72e2"
+      ],
+      "content-length": [
+        "1066"
+      ],
+      "x-envoy-upstream-service-time": [
+        "29"
+      ],
+      "date": [
+        "Mon, 04 Sep 2023 08:53:16 GMT"
+      ],
+      "server": [
+        "ATS"
+      ],
+      "x-envoy-decorator-operation": [
+        "finance-chart-api--mtls-production-ir2.finance-k8s.svc.yahoo.local:4080/*"
+      ],
+      "age": [
+        "0"
+      ],
+      "strict-transport-security": [
+        "max-age=31536000"
+      ],
+      "referrer-policy": [
+        "no-referrer-when-downgrade"
+      ],
+      "x-frame-options": [
+        "SAMEORIGIN"
+      ],
+      "connection": [
+        "close"
+      ],
+      "expect-ct": [
+        "max-age=31536000, report-uri=\"http://csp.yahoo.com/beacon/csp?src=yahoocom-expect-ct-report-only\""
+      ],
+      "x-xss-protection": [
+        "1; mode=block"
+      ],
+      "x-content-type-options": [
+        "nosniff"
+      ]
+    },
+    "body": "{\"chart\":{\"result\":[{\"meta\":{\"currency\":\"EUR\",\"symbol\":\"WSU.DE\",\"exchangeName\":\"GER\",\"instrumentType\":\"EQUITY\",\"firstTradeDate\":910598400,\"regularMarketTime\":1693812773,\"gmtoffset\":7200,\"timezone\":\"CEST\",\"exchangeTimezoneName\":\"Europe/Berlin\",\"regularMarketPrice\":33.35,\"chartPreviousClose\":34.25,\"priceHint\":2,\"currentTradingPeriod\":{\"pre\":{\"timezone\":\"CEST\",\"start\":1693803600,\"end\":1693810800,\"gmtoffset\":7200},\"regular\":{\"timezone\":\"CEST\",\"start\":1693810800,\"end\":1693841400,\"gmtoffset\":7200},\"post\":{\"timezone\":\"CEST\",\"start\":1693841400,\"end\":1693852200,\"gmtoffset\":7200}},\"dataGranularity\":\"1d\",\"range\":\"\",\"validRanges\":[\"1d\",\"5d\",\"1mo\",\"3mo\",\"6mo\",\"1y\",\"2y\",\"5y\",\"10y\",\"ytd\",\"max\"]},\"timestamp\":[1691132400,1691391600,1691478000],\"indicators\":{\"quote\":[{\"high\":[34.54999923706055,null,34.20000076293945],\"low\":[34.099998474121094,null,32.900001525878906],\"close\":[34.45000076293945,null,33.20000076293945],\"volume\":[1251,null,10846],\"open\":[34.25,null,34.04999923706055]}],\"adjclose\":[{\"adjclose\":[34.45000076293945,null,33.20000076293945]}]}}],\"error\":null}}"
+  }
+}
\ No newline at end of file