diff --git a/src/index.tsx b/src/index.tsx
index 17488ff..81538fa 100644
--- a/src/index.tsx
+++ b/src/index.tsx
@@ -15,6 +15,13 @@ type ChartData = {
   dataPoints?: { [x: string]: number };
   start?: Date;
   end?: Date;
+  yMarkers?: Array<{ label: string; value: number; options?: object; }>;
+  yRegions?: Array<{
+    label: string;
+    start: number;
+    end: number;
+    options?: object;
+  }>;
 };
 
 type SelectEvent = {