diff --git a/Axel/src/de/hs_mannheim/informatik/spreadsheet/Spreadsheet.java b/Axel/src/de/hs_mannheim/informatik/spreadsheet/Spreadsheet.java
index eae19ed..68dc7c5 100644
--- a/Axel/src/de/hs_mannheim/informatik/spreadsheet/Spreadsheet.java
+++ b/Axel/src/de/hs_mannheim/informatik/spreadsheet/Spreadsheet.java
@@ -5,6 +5,7 @@ import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.io.PrintWriter;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Scanner;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
@@ -195,7 +196,18 @@ public class Spreadsheet {
 
 
 		else if (formula.startsWith("STABW("))  // e.g. STABW(C6:D8) -> Standardabweichung
-			result = "TODO"; // TODO
+			if(formula.length()<13)
+				result = "" + standardDeviation(substringStartCell1, substringEndCell);
+			else if(formula.length()<14&&substringStart2.contains(":"))
+				result = "" + standardDeviation(substringStartCell1, substringEndCell);
+			else if(formula.length()<14&&!substringStart2.contains(":"))
+				result = "" + standardDeviation(substringStart2, substringEndCell);
+			else if(formula.length()<15)
+				result = "" + standardDeviation(substringStart2, substringEndCell);
+			else
+				result = "0";
+
+
 		else if (formula.startsWith("MIN("))  // e.g. MIN(C13:H13) -> größter Wert
 			result = "TODO"; // TODO
 		else if (formula.startsWith("MAX("))  // e.g. MAX(A1:A10) -> Standardabweichung
@@ -265,7 +277,58 @@ public class Spreadsheet {
 					cellNames.add(getCellName(r, c));
 				} catch (NumberFormatException n){}
 		avg /= counter;
-		return 0;
+		//average
+
+		ArrayList<String> copyCellNames = new ArrayList<>(cellNames);
+		double[] frequency = new double[cellNames.size()];
+		Arrays.fill(frequency,1);
+		ArrayList<Double> relativeFrequency = new ArrayList<>();
+		double mem = 0;
+
+		for(int i = 0; i< cellNames.size(); i++) {
+			for(int t = 0; t<cellNames.size(); t++){
+				if(((get(cellNames.get(i)).isEmpty())&&!(get(cellNames.get(t)).isEmpty()))&&(Double.parseDouble(get(cellNames.get(t)))==0)&&(t!=i)){
+					cellNames.remove(t);
+					frequency[i]++;
+					t = 0;
+				}else if((!(get(cellNames.get(i)).isEmpty())&&(get(cellNames.get(t)).isEmpty()))&&(Double.parseDouble(get(cellNames.get(i)))==0)&&(t!=i)){
+					cellNames.remove(t);
+					frequency[i]++;
+					t = 0;
+				}else if((get(cellNames.get(i)).isEmpty())&&(get(cellNames.get(t)).isEmpty())&&(t!=i)){
+					cellNames.remove(t);
+					frequency[i]++;
+					t = 0;
+				}else if((t!=i)&&(Double.parseDouble(get(cellNames.get(i))))==(Double.parseDouble(get(cellNames.get(t))))){
+					cellNames.remove(t);
+					frequency[i] ++;
+					t = 0;
+				}
+			}
+		}
+		//delete all duplicates
+
+		for(int i = 0; i< cellNames.size(); i++)
+			relativeFrequency.add(i,frequency[i]/copyCellNames.size());
+
+
+		if(get(cellNames.get(0)).isEmpty())
+			mem = ((0 - avg)*(0 - avg))
+					* relativeFrequency.get(0);
+
+		else
+			mem = ((Double.parseDouble(get(cellNames.get(0))) - avg)*(Double.parseDouble(get(cellNames.get(0))) - avg))
+					* relativeFrequency.get(0);
+
+		for(int i = 1; i<cellNames.size(); i++)
+			if(get(cellNames.get(i)).isEmpty())
+				mem += ((0 - avg)*(0 - avg))
+						* relativeFrequency.get(i);
+			else
+				mem += ((Double.parseDouble(get(cellNames.get(i))) - avg)*(Double.parseDouble(get(cellNames.get(i))) - avg))
+						* relativeFrequency.get(i);
+		return Math.sqrt(mem);
+		//standardDeviation formula
 	}
 
 	/**