diff --git a/metrics/grafana/ticdc.json b/metrics/grafana/ticdc.json
index 79e605dd679..c6eb69a45d1 100644
--- a/metrics/grafana/ticdc.json
+++ b/metrics/grafana/ticdc.json
@@ -7726,7 +7726,7 @@
           "dashLength": 10,
           "dashes": false,
           "datasource": "${DS_TEST-CLUSTER}",
-          "description": "The compression ratio times 100 of record batches for all topics.",
+          "description": "The compression ratio times 100 of record batches for all topics. Compression ratio = Size of original data / Size of compressed data * 100",
           "fieldConfig": {
             "defaults": {},
             "overrides": []