diff --git a/TermTk/TTkLayouts/layout.py b/TermTk/TTkLayouts/layout.py
index 6f8b7331..bd73506f 100644
--- a/TermTk/TTkLayouts/layout.py
+++ b/TermTk/TTkLayouts/layout.py
@@ -269,21 +269,15 @@ class TTkLayout(TTkLayoutItem):
         return None
 
     def raiseWidget(self, widget):
-        maxz = 0
         item = self.findBranchWidget(widget)
-        for i in self._items:
-            maxz=max(i.z+1,maxz)
-        item.z = maxz
+        item.z = max([i.z for i in self._items])+1
         if item.layoutItemType == TTkK.LayoutItem:
             item.raiseWidget(widget)
         self._zSortItems()
 
     def lowerWidget(self, widget):
-        minz = 0
         item = self.findBranchWidget(widget)
-        for i in self._items:
-            minz=min(i.z-1,minz)
-        item.z = minz
+        item.z = min([i.z for i in self._items])-1
         if item.layoutItemType == TTkK.LayoutItem:
             item.lowerWidget(widget)
         self._zSortItems()
diff --git a/tests/timeit/02.array.copy.py b/tests/timeit/02.array.copy.py
index a8f7e756..0201cf32 100644
--- a/tests/timeit/02.array.copy.py
+++ b/tests/timeit/02.array.copy.py
@@ -67,19 +67,19 @@ def test1():
     _colors = [baseColors.copy() for _ in range(h)]
     return len(_data), len(_colors)
 
-def test2():
+def test2(): # tbd
     for i in range(len(doc1)):
         if i >= len(doc2) or doc2[-i-1] != doc1[-i-1]:
             return i
     return None
 
-def test3():
+def test3(): # tbd
     for i,(a,b) in enumerate(zip(reversed(doc1),reversed(doc2))):
         if a!=b:
             return f"{i}\n - {a}\n - {b}"
     return None
 
-def test4():
+def test4(): # tbd
     for i,(a,b) in enumerate(zip(doc1,doc2)):
         if a!=b:
             return f"{i}\n - {a}\n - {b}"
diff --git a/tests/timeit/03.max.min.py b/tests/timeit/03.max.min.py
new file mode 100644
index 00000000..abaf9e44
--- /dev/null
+++ b/tests/timeit/03.max.min.py
@@ -0,0 +1,86 @@
+#!/usr/bin/env python3
+
+# MIT License
+#
+# Copyright (c) 2021 Eugenio Parodi <ceccopierangiolieugenio AT googlemail DOT com>
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+import sys, os
+
+import timeit
+import random
+
+
+sys.path.append(os.path.join(sys.path[0],'../..'))
+import TermTk as ttk
+
+words = ["Lorem", "ipsum", "dolor", "sit", "amet,", "consectetur", "adipiscing", "elit,", "sed", "do", "eiusmod", "tempor", "incididunt", "ut", "labore", "et", "dolore", "magna", "aliqua.", "Ut", "enim", "ad", "minim", "veniam,", "quis", "nostrud", "exercitation", "ullamco", "laboris", "nisi", "ut", "aliquip", "ex", "ea", "commodo", "consequat.", "Duis", "aute", "irure", "dolor", "in", "reprehenderit", "in", "voluptate", "velit", "esse", "cillum", "dolore", "eu", "fugiat", "nulla", "pariatur.", "Excepteur", "sint", "occaecat", "cupidatat", "non", "proident,", "sunt", "in", "culpa", "qui", "officia", "deserunt", "mollit", "anim", "id", "est", "laborum."]
+
+def getWords(n):
+    www = [random.choice(words) for _ in range(n)]
+    return " ".join(www)
+def getSentence(a,b,i):
+    return " ".join([f"{i} "]+[getWords(random.randint(1,4)) for i in range(0,random.randint(a,b))])
+
+doc1 = [ getSentence(3,10,i) for i in range(10000) ]
+
+doc2 = doc1.copy()
+doc2[5000:5050] = [ getSentence(3,10,i) for i in range(50) ]
+
+
+nn = 1000
+
+class I():
+    def __init__(self, i):
+        self.z = i
+
+ii = [ I(random.randint(0,10000)) for _ in range(nn)]
+
+
+def test():
+    minz = 0
+    for i in ii:
+        minz=min(i.z-1,minz)
+    return minz
+
+def test1():
+    return min([i.z-1 for i in ii])
+
+def test2():
+    return min([i.z for i in ii])-1
+
+def test3(): # tbd
+    return 0
+
+def test4(): # tbd
+    return 0
+
+loop = 1000
+
+result = timeit.timeit('test()', globals=globals(), number=loop)
+print(f"{result / loop:.10f} - {result / loop} {test()}")
+result = timeit.timeit('test1()', globals=globals(), number=loop)
+print(f"{result / loop:.10f} - {result / loop} {test1()}")
+result = timeit.timeit('test2()', globals=globals(), number=loop)
+print(f"{result / loop:.10f} - {result / loop} {test2()}")
+result = timeit.timeit('test3()', globals=globals(), number=loop)
+print(f"{result / loop:.10f} - {result / loop} {test3()}")
+result = timeit.timeit('test4()', globals=globals(), number=loop)
+print(f"{result / loop:.10f} - {result / loop} {test4()}")