diff --git a/IRaCIS.Core.Application/Service/Reading/ReadingCalculateService.cs b/IRaCIS.Core.Application/Service/Reading/ReadingCalculateService.cs
index 071b417b8..4dde05063 100644
--- a/IRaCIS.Core.Application/Service/Reading/ReadingCalculateService.cs
+++ b/IRaCIS.Core.Application/Service/Reading/ReadingCalculateService.cs
@@ -478,9 +478,9 @@ namespace IRaCIS.Core.Application.Service
 		}
 		#endregion
 
-		#region 与整个访视期间最低点相比增加的百分比
+		#region 与基线访视相比SOD变化百分比
 		/// <summary>
-		/// 与整个访视期间最低点相比增加的百分比
+		/// 与基线访视相比SOD变化百分比
 		/// </summary>
 		/// <param name="inDto"></param>
 		/// <returns></returns>
@@ -501,7 +501,7 @@ namespace IRaCIS.Core.Application.Service
 			}
 			else
 			{
-				return decimal.Round(thisSOD.NullChange0() * 100 / baseLineSOD, 2);
+				return decimal.Round((thisSOD.NullChange0()- baseLineSOD) * 100 / baseLineSOD, 2);
 			}
 		}
 		#endregion