diff --git a/AsbCloudApp/Data/WellOperationDto.cs b/AsbCloudApp/Data/WellOperationDto.cs
index b3dc537c..31b50243 100644
--- a/AsbCloudApp/Data/WellOperationDto.cs
+++ b/AsbCloudApp/Data/WellOperationDto.cs
@@ -89,11 +89,6 @@ namespace AsbCloudApp.Data
         [DateValidation(GtDate = "2010-01-01T00:00:00")]
         public DateTime DateStart { get; set; }
 
-        /// <summary>
-        /// Дата окончания операции
-        /// </summary>
-        public DateTime DateEnd => DateStart.AddHours(DurationHours);
-
         /// <summary>
         /// Продолжительность, часы
         /// </summary>
diff --git a/AsbCloudInfrastructure/Services/WellOperationService/OperationsStatService.cs b/AsbCloudInfrastructure/Services/WellOperationService/OperationsStatService.cs
index 465f98f9..8be58bc6 100644
--- a/AsbCloudInfrastructure/Services/WellOperationService/OperationsStatService.cs
+++ b/AsbCloudInfrastructure/Services/WellOperationService/OperationsStatService.cs
@@ -173,43 +173,49 @@ namespace AsbCloudInfrastructure.Services.WellOperationService
             var timezoneOffsetH = wellService.GetTimezone(well.Id).Hours;
             statWellDto.Sections = CalcSectionsStats(wellOperations, timezoneOffsetH);
             statWellDto.Total = GetStatTotal(wellOperations, well.IdState, timezoneOffsetH);
-            statWellDto.TvdLagPercent = CalcTvdLagPercent(well.IdTelemetry, wellOperations
-                .Select(x => x.Adapt<WellOperationDto>()));
+            statWellDto.TvdLagPercent = CalcTvdLagPercent(well.IdTelemetry, wellOperations);
 
             return statWellDto;
         }
 
-		private double? CalcTvdLagPercent(int? idTelemetry, IEnumerable<WellOperationDto> wellOperations)
-		{
-			if (!idTelemetry.HasValue)
-				return null;
-
+        private double? CalcTvdLagPercent(int? idTelemetry, IOrderedEnumerable<WellOperation> wellOperations)
+        {
             var currentDate = DateTime.UtcNow;
+            
+            var wellDepth = wellOperations
+                .LastOrDefault(o => o.IdType == WellOperation.IdOperationTypeFact)?.DepthEnd;
+            
+            if (idTelemetry.HasValue)
+                wellDepth = telemetryDataCache.GetLastOrDefault(idTelemetry.Value)?.WellDepth;
 
-			var lastFactOperation = telemetryDataCache.GetLastOrDefault(idTelemetry.Value);
-			
-			wellOperations = wellOperations
-				.Where(o => o.IdType == WellOperation.IdOperationTypePlan)
-				.OrderBy(o => o.DateEnd);
+            var planOperations = wellOperations
+                .Where(o => o.IdType == WellOperation.IdOperationTypePlan)
+                .OrderBy(o => o.DateStart.AddHours(o.DurationHours));
 
-			var wellOperationFrom = wellOperations
-				.LastOrDefault(o => o.DateEnd <= currentDate);
+            var wellOperationFrom = planOperations
+                .LastOrDefault(o => o.DateStart.AddHours(o.DurationHours) <= currentDate);
 
-            var wellOperationTo = wellOperations
-                .FirstOrDefault(o => o.DateEnd >= currentDate);
+            var wellOperationTo = planOperations
+                .FirstOrDefault(o => o.DateStart >= currentDate);
 
             var wellOperationDepthFrom = wellOperationFrom?.DepthEnd;
-			var wellOperationDepthTo = wellOperationTo?.DepthStart ?? wellOperationDepthFrom;
+            var wellOperationDepthTo = wellOperationTo?.DepthStart ?? wellOperationDepthFrom;
 
-			var wellOperationDateFrom = wellOperationFrom?.DateEnd;
-			var wellOperationDateTo = wellOperationTo?.DateStart ?? wellOperationDateFrom;
+            var wellOperationDateFrom = wellOperationFrom?.DateStart.AddHours(wellOperationFrom.DurationHours);
+            var wellOperationDateTo = wellOperationTo?.DateStart ?? currentDate;
             
-            var planDepth = (wellOperationDateTo - wellOperationDateFrom)?.TotalHours *
-				(wellOperationDepthTo - wellOperationDepthFrom) /
-				(currentDate - wellOperationDateFrom)?.TotalHours + wellOperationDepthFrom;
+            if (wellOperationDateTo <= wellOperationDateFrom ||
+                currentDate <= wellOperationDateFrom ||
+                (wellOperationDateTo - wellOperationDateFrom)?.TotalHours is null or 0)
+                return null;
 
-			return (1 - lastFactOperation?.WellDepth / planDepth) * 100;
-		}
+            var planDepth = (currentDate - wellOperationDateFrom)?.TotalHours * 
+                            (wellOperationDepthTo - wellOperationDepthFrom) / 
+                            (wellOperationDateTo - wellOperationDateFrom)?.TotalHours + 
+                            wellOperationDepthFrom;
+
+            return (1 - wellDepth / planDepth) * 100;
+        }
 
         private IEnumerable<StatSectionDto> CalcSectionsStats(IEnumerable<WellOperation> operations, double timezoneOffsetH)
         {