diff --git a/components/fpspreadsheet/fpsfunc.pas b/components/fpspreadsheet/fpsfunc.pas
index ae49a7b00..7d9ff2f72 100644
--- a/components/fpspreadsheet/fpsfunc.pas
+++ b/components/fpspreadsheet/fpsfunc.pas
@@ -11,6 +11,8 @@ type
   TsArgumentType = (atCell, atCellRange, atNumber, atString,
     atBool, atError, atEmpty);
 
+  TsArgumentTypes = set of TsArgumentType;
+
   TsArgBoolArray  = array of boolean;
   TsArgNumberArray = array of double;
   TsArgStringArray   = array of string;
@@ -128,6 +130,7 @@ function fpsYEAR        (Args: TsArgumentStack; NumArgs: Integer): TsArgument;
 function fpsAVEDEV      (Args: TsArgumentStack; NumArgs: Integer): TsArgument;
 function fpsAVERAGE     (Args: TsArgumentStack; NumArgs: Integer): TsArgument;
 function fpsCOUNT       (Args: TsArgumentStack; NumArgs: Integer): TsArgument;
+function fpsCOUNTA      (Args: TsArgumentStack; NumArgs: Integer): TsArgument;
 function fpsCOUNTBLANK  (Args: TsArgumentStack; NumArgs: Integer): TsArgument;
 function fpsCOUNTIF     (Args: TsArgumentStack; NumArgs: Integer): TsArgument;
 function fpsMAX         (Args: TsArgumentStack; NumArgs: Integer): TsArgument;
@@ -1534,7 +1537,7 @@ end;
 function fpsCOUNT(Args: TsArgumentStack; NumArgs: Integer): TsArgument;
 { counts the number of cells that contain numbers as well as the number of
   arguments that contain numbers.
-  COUNT( argument1, [argument2, ... argument_n] )
+  COUNT( argument1 [, argument2, ... argument_n] )
 }
 var
   data: TsArgNumberArray;
@@ -1543,6 +1546,38 @@ begin
     Result := CreateNumberArg(Length(data));
 end;
 
+function fpsCOUNTA(Args: TsArgumentStack; NumArgs: Integer): TsArgument;
+// COUNTA (argument1 [, argument2, ... argument_n] )
+// Counts the number of non-empty cells specified by arguments of misc type.
+var
+  arg: TsArgument;
+  counter: Integer;
+  r, c: Integer;
+  cell: PCell;
+  n: Integer;
+begin
+  n := 0;
+  // The order of arguments is not important for counting --> we just pop them from the stack.
+  for counter := 1 to NumArgs do begin
+    arg := Args.Pop;
+    case arg.ArgumentType of
+      atCell:
+        if arg.Cell^.ContentType <> cctEmpty then inc(n);
+      atCellRange:
+        for r := arg.FirstRow to arg.LastRow do
+          for c := arg.FirstCol to arg.LastCol do begin
+            cell := arg.Worksheet.FindCell(r, c);
+            if (cell <> nil) and (cell^.ContentType <> cctEmpty) then inc(n);
+          end;
+      atString:
+        if arg.StringValue <> '' then inc(n);
+      atNumber, atBool, atError:
+        inc(n);
+    end;
+  end;
+  Result := CreateNumberArg(n);
+end;
+
 function fpsCOUNTBLANK(Args: TsArgumentStack; NumArgs: Integer): TsArgument;
 // COUNTBLANK( range )
 // counts the number of empty cells in a range.
diff --git a/components/fpspreadsheet/fpspreadsheet.pas b/components/fpspreadsheet/fpspreadsheet.pas
index 6025a3baa..abc6b5fe7 100755
--- a/components/fpspreadsheet/fpspreadsheet.pas
+++ b/components/fpspreadsheet/fpspreadsheet.pas
@@ -1152,7 +1152,7 @@ var
     (Symbol:'<';         MinParams:2; MaxParams:2;  Func:fpsLess),              // fekLess
     (Symbol:'<=';        MinParams:2; MaxParams:2;  Func:fpsLessEqual),         // fekLessEqual
     (Symbol:'<>';        MinParams:2; MaxParams:2;  Func:fpsNotEqual),          // fekNotEqual
-    (Symbol:'';          MinParams:1; MaxParams:1;  Func:nil),   // fekParen
+    (Symbol:'';          MinParams:1; MaxParams:1;  Func:nil),                  // fekParen   -- no need to calculate!
   { math }
     (Symbol:'ABS';       MinParams:1; MaxParams:1;  Func:fpsABS),               // fekABS
     (Symbol:'ACOS';      MinParams:1; MaxParams:1;  Func:fpsACOS),              // fekACOS
@@ -1203,7 +1203,7 @@ var
     (Symbol:'CHIDIST';   MinParams:2; MaxParams:2;  Func:nil),   // fekCHIDIST
     (Symbol:'CHIINV';    MinParams:2; MaxParams:2;  Func:nil),   // fekCHIINV
     (Symbol:'COUNT';     MinParams:0; MaxParams:30; Func:fpsCOUNT),             // fekCOUNT
-    (Symbol:'COUNTA';    MinParams:0; MaxParams:30; Func:nil),  // fekCOUNTA
+    (Symbol:'COUNTA';    MinParams:0; MaxParams:30; Func:fpsCOUNTA),            // fekCOUNTA
     (Symbol:'COUNTBLANK';MinParams:1; MaxParams:1;  Func:fpsCOUNTBLANK),        // fekCOUNTBLANK
     (Symbol:'COUNTIF';   MinParams:2; MaxParams:2;  Func:fpsCOUNTIF),           // fekCOUNTIF
     (Symbol:'MAX';       MinParams:1; MaxParams:30; Func:fpsMAX),               // fekMAX
diff --git a/components/fpspreadsheet/tests/spreadtestgui.lpi b/components/fpspreadsheet/tests/spreadtestgui.lpi
index 505633548..ed06b19d3 100644
--- a/components/fpspreadsheet/tests/spreadtestgui.lpi
+++ b/components/fpspreadsheet/tests/spreadtestgui.lpi
@@ -80,7 +80,6 @@
       <Unit1>
         <Filename Value="datetests.pas"/>
         <IsPartOfProject Value="True"/>
-        <UnitName Value="datetests"/>
       </Unit1>
       <Unit2>
         <Filename Value="stringtests.pas"/>
@@ -89,12 +88,10 @@
       <Unit3>
         <Filename Value="numberstests.pas"/>
         <IsPartOfProject Value="True"/>
-        <UnitName Value="numberstests"/>
       </Unit3>
       <Unit4>
         <Filename Value="manualtests.pas"/>
         <IsPartOfProject Value="True"/>
-        <UnitName Value="manualtests"/>
       </Unit4>
       <Unit5>
         <Filename Value="testsutility.pas"/>
diff --git a/components/fpspreadsheet/tests/testcases_calcrpnformula.inc b/components/fpspreadsheet/tests/testcases_calcrpnformula.inc
index 439a4894f..718d1c3be 100644
--- a/components/fpspreadsheet/tests/testcases_calcrpnformula.inc
+++ b/components/fpspreadsheet/tests/testcases_calcrpnformula.inc
@@ -1286,6 +1286,42 @@
   SetLength(sollValues, Row+1);
   sollValues[Row] := CreateNumberArg(2);
 
+  // COUNTA
+  MyWorksheet.WriteUTF8Text(Row, 0, '=COUNTA(1, 1.1, 1.2, 0.9, 0.8)');
+  MyWorksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
+    RPNNumber(1.0,
+    RPNNumber(1.1,
+    RPNNumber(1.2,
+    RPNNumber(0.9,
+    RPNNumber(0.8,
+    RPNFunc(fekCOUNTA, 5, nil))))))));
+  SetLength(sollValues, Row+1);
+  sollValues[Row] := CreateNumberArg(5);
+
+  MyWorksheet.WriteUTF8Text(Row, 0, '=COUNTA(1, 1.1, 1.2, 0.9, 0.8, "A", "B")');
+  MyWorksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
+    RPNNumber(1.0,
+    RPNNumber(1.1,
+    RPNNumber(1.2,
+    RPNNumber(0.9,
+    RPNNumber(0.8,
+    RPNString('A',
+    RPNString('B',
+    RPNFunc(fekCOUNTA, 7, nil))))))))));
+  SetLength(sollValues, Row+1);
+  sollValues[Row] := CreateNumberArg(7);
+
+  inc(Row);
+  MyWorksheet.WriteUTF8Text(Row, 0, '=COUNTA(A1:C2,1,2,"A")');
+  MyWorksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
+    RPNCellRange('A1:C2',
+    RPNNumber(1,
+    RPNNumber(2,
+    RPNString('A',
+    RPNFunc(fekCOUNTA, 4, nil)))))));
+  SetLength(sollValues, Row+1);
+  sollValues[Row] := CreateNumberArg(7);
+
   if AFormat <> sfExcel2 then begin
     // COUNTBLANK
     inc(Row);