diff --git a/marker_analysis/tests/data/sample_markers.json b/marker_analysis/tests/data/sample_markers.json
new file mode 100644
index 0000000..2cb0edf
--- /dev/null
+++ b/marker_analysis/tests/data/sample_markers.json
@@ -0,0 +1,42 @@
+[
+  {
+    "marker_id": "corr_001_pre",
+    "timestamp": 1710000000.001,
+    "status": "write_pre"
+  },
+  {
+    "marker_id": "corr_001_post",
+    "timestamp": 1710000000.305,
+    "status": "write_post"
+  },
+  {
+    "marker_id": "corr_002_pre",
+    "timestamp": 1710000001.002,
+    "status": "write_pre"
+  },
+  {
+    "marker_id": "corr_002_post",
+    "timestamp": 1710000001.289,
+    "status": "write_post"
+  },
+  {
+    "marker_id": "corr_002_read1",
+    "timestamp": 1710000001.310,
+    "status": "read_between_steps"
+  },
+  {
+    "marker_id": "corr_003_pre",
+    "timestamp": 1710000002.001,
+    "status": "write_pre"
+  },
+  {
+    "marker_id": "corr_003_read1",
+    "timestamp": 1710000002.050,
+    "status": "read_between_steps"
+  },
+  {
+    "marker_id": "corr_004_post",
+    "timestamp": 1710000003.400,
+    "status": "write_post"
+  }
+]
\ No newline at end of file