diff --git a/src/MiniExcel.OpenXml/Templates/OpenXmlTemplate.Impl.cs b/src/MiniExcel.OpenXml/Templates/OpenXmlTemplate.Impl.cs
index e021acb0..6eca0286 100644
--- a/src/MiniExcel.OpenXml/Templates/OpenXmlTemplate.Impl.cs
+++ b/src/MiniExcel.OpenXml/Templates/OpenXmlTemplate.Impl.cs
@@ -526,7 +526,7 @@ await writer.WriteAsync($"<{prefix}sheetData>"
                 ProcessFormulas(rowXml, newRowIndex);
                 await writer.WriteAsync(CleanXml(rowXml, endPrefix).ToString()
 #if NET5_0_OR_GREATER
-                            .AsMemory(), cancellationToken
+                    .AsMemory(), cancellationToken
 #endif
                 ).ConfigureAwait(false);
 
@@ -549,7 +549,7 @@ await writer.WriteAsync(CleanXml(rowXml, endPrefix).ToString()
 
         await writer.WriteAsync($"</{prefix}sheetData>"
 #if NET7_0_OR_GREATER
-                    .AsMemory(), cancellationToken
+            .AsMemory(), cancellationToken
 #endif
         ).ConfigureAwait(false);
 
@@ -628,10 +628,20 @@ class GenerateCellValuesContext
 
     //todo: refactor in a way that needs less parameters
     [CreateSyncVersion]
-    private async Task<GenerateCellValuesContext> GenerateCellValuesAsync(GenerateCellValuesContext generateCellValuesContext, string endPrefix, StreamWriter writer,
-        StringBuilder rowXml, int mergeRowCount, bool isHeaderRow,
-        XRowInfo rowInfo, XmlElement row, int groupingRowDiff,
-        string innerXml, StringBuilder outerXmlOpen, XmlElement rowElement, CancellationToken cancellationToken = default)
+    private async Task<GenerateCellValuesContext> GenerateCellValuesAsync(
+        GenerateCellValuesContext generateCellValuesContext, 
+        string endPrefix, 
+        StreamWriter writer,
+        StringBuilder rowXml, 
+        int mergeRowCount, 
+        bool isHeaderRow, 
+        XRowInfo rowInfo, 
+        XmlElement row, 
+        int groupingRowDiff,
+        string innerXml, 
+        StringBuilder outerXmlOpen, 
+        XmlElement rowElement, 
+        CancellationToken cancellationToken = default)
     {
         var rowIndexDiff = generateCellValuesContext.rowIndexDiff;
         var headerDiff = generateCellValuesContext.headerDiff;
@@ -698,27 +708,24 @@ private async Task<GenerateCellValuesContext> GenerateCellValuesAsync(GenerateCe
                         .Replace(")", "")
                         .Split(' ');
 
-                    object value;
+                    object? value;
                     if (rowInfo.IsDictionary)
                     {
-                        value = dict[newLines[0]];
+                        value = dict![newLines[0]];
                     }
                     else if (rowInfo.IsDataTable)
                     {
-                        value = dataRow[newLines[0]];
+                        value = dataRow![newLines[0]];
                     }
                     else
                     {
-                        value = string.Empty;
                         var prop = rowInfo.PropsMap[newLines[0]];
-                        if (prop.PropertyInfoOrFieldInfo == PropertyInfoOrFieldInfo.PropertyInfo)
+                        value = prop.PropertyInfoOrFieldInfo switch
                         {
-                            value = prop.PropertyInfo.GetValue(item);
-                        }
-                        else if (prop.PropertyInfoOrFieldInfo == PropertyInfoOrFieldInfo.FieldInfo)
-                        {
-                            value = prop.FieldInfo.GetValue(item);
-                        }
+                            PropertyInfoOrFieldInfo.PropertyInfo => prop.PropertyInfo.GetValue(item),
+                            PropertyInfoOrFieldInfo.FieldInfo => prop.FieldInfo.GetValue(item),
+                            _ => string.Empty
+                        };
                     }
 
                     var evaluation = EvaluateStatement(value, newLines[1], newLines[2]);
@@ -750,7 +757,7 @@ private async Task<GenerateCellValuesContext> GenerateCellValuesAsync(GenerateCe
             {
                 var replacements = new Dictionary<string, string>();
 #if NETCOREAPP3_0_OR_GREATER
-                string MatchDelegate(Match x) => CollectionExtensions.GetValueOrDefault(replacements, x.Groups[1].Value, "");
+                string MatchDelegate(Match x) => replacements.GetValueOrDefault(x.Groups[1].Value, "");
 #else
                 string MatchDelegate(Match x) => replacements.TryGetValue(x.Groups[1].Value, out var repl) ? repl : "";
 #endif
@@ -763,12 +770,12 @@ private async Task<GenerateCellValuesContext> GenerateCellValuesAsync(GenerateCe
                     object? cellValue;
                     if (rowInfo.IsDictionary)
                     {
-                        if (!dict.TryGetValue(prop.Key, out cellValue))
+                        if (!dict!.TryGetValue(prop.Key, out cellValue))
                             continue;
                     }
                     else if (rowInfo.IsDataTable)
                     {
-                        cellValue = dataRow[prop.Key];
+                        cellValue = dataRow![prop.Key];
                     }
                     else
                     {
@@ -782,7 +789,7 @@ private async Task<GenerateCellValuesContext> GenerateCellValuesAsync(GenerateCe
                         ? prop.Value.UnderlyingTypePropType
                         : Nullable.GetUnderlyingType(propInfo.PropertyType) ?? propInfo.PropertyType;
 
-                    string cellValueStr;
+                    string? cellValueStr;
                     if (type == typeof(bool))
                     {
                         cellValueStr = (bool)cellValue ? "1" : "0";
@@ -791,7 +798,7 @@ private async Task<GenerateCellValuesContext> GenerateCellValuesAsync(GenerateCe
                     {
                         cellValueStr = ConvertToDateTimeString(propInfo, cellValue);
                     }
-                    else if (type?.IsEnum ?? false)
+                    else if (type?.IsEnum is true)
                     {
                         var description = CustomPropertyHelper.GetDescriptionAttribute(type, cellValue);
                         cellValueStr = XmlHelper.EncodeXml(description);
@@ -799,15 +806,21 @@ private async Task<GenerateCellValuesContext> GenerateCellValuesAsync(GenerateCe
                     else
                     {
                         cellValueStr = XmlHelper.EncodeXml(cellValue?.ToString());
-                        if (!isDictOrTable && TypeHelper.IsNumericType(type))
+                        if (TypeHelper.IsNumericType(type))
                         {
                             if (decimal.TryParse(cellValueStr, out var decimalValue))
                                 cellValueStr = decimalValue.ToString(CultureInfo.InvariantCulture);
                         }
                     }
 
-                    replacements[key] = cellValueStr;
-                    rowXml.Replace($"@header{{{{{key}}}}}", cellValueStr);
+                    // escaping formulas
+                    var tempReplacement = cellValueStr ?? "";
+                    var replacementValue = tempReplacement.StartsWith("$=") || tempReplacement.StartsWith("=")
+                        ? $"&apos;{tempReplacement}" 
+                        : tempReplacement;
+                    
+                    replacements[key] = replacementValue;
+                    rowXml.Replace($"@header{{{{{key}}}}}", replacementValue);
 
                     if (isHeaderRow && row.InnerText.Contains(key))
                     {
@@ -915,7 +928,7 @@ await writer.WriteAsync(CleanXml(newRow.OuterXml, endPrefix)
             }
         }
 
-        return new GenerateCellValuesContext()
+        return new GenerateCellValuesContext
         {
             currentHeader = currentHeader,
             headerDiff = headerDiff,
@@ -1067,8 +1080,8 @@ private void ProcessFormulas(StringBuilder rowXml, int rowIndex)
                  <c r="C8" s="3">
                     <f>SUM(C2:C7)</f>
                 </c>
-                 */
-            var vs = c.SelectNodes("x:v", Ns);
+            */
+            var vs = c.SelectNodes("x:is", Ns);
             foreach (XmlElement v in vs)
             {
                 if (!v.InnerText.StartsWith("$="))
diff --git a/tests/MiniExcel.OpenXml.Tests/MiniExcelIssueTests.cs b/tests/MiniExcel.OpenXml.Tests/MiniExcelIssueTests.cs
index fd6b7e91..5d051b32 100644
--- a/tests/MiniExcel.OpenXml.Tests/MiniExcelIssueTests.cs
+++ b/tests/MiniExcel.OpenXml.Tests/MiniExcelIssueTests.cs
@@ -3784,4 +3784,27 @@ public void TestIssue888_ShouldIgnoreFrame()
         Assert.Equal(dataInSheet, dataRead);
     }
 
+    [Fact]
+    public void TestIssue915()
+    {
+        var templatePath = PathHelper.GetFile("xlsx/TestIssue915.xlsx");
+        var value = new Dictionary<string,object>
+        {
+            ["Data"] = new[] 
+            { 
+                new { Name = "Hill", Altitude = 6m }, 
+                new { Name = "Mount", Altitude = 7.4m }, 
+                new { Name = "Peak", Altitude = 8.6m } 
+            }
+        };
+        
+        using var path = AutoDeletingPath.Create();
+        _excelTemplater.ApplyTemplate(path.ToString(), templatePath, value);
+
+        var result = _excelImporter.Query(path.ToString(), true).ToList();
+        
+        Assert.Equal(6, result[0].Altitude);
+        Assert.Equal(7.4, result[1].Altitude);
+        Assert.Equal(8.6, result[2].Altitude);
+    }
 }
\ No newline at end of file
diff --git a/tests/data/xlsx/TestIssue915.xlsx b/tests/data/xlsx/TestIssue915.xlsx
new file mode 100644
index 00000000..476fd0ef
Binary files /dev/null and b/tests/data/xlsx/TestIssue915.xlsx differ