diff --git a/lecturecommon.sty b/lecturecommon.sty
index f477cb0..757a78b 100644
--- a/lecturecommon.sty
+++ b/lecturecommon.sty
@@ -154,8 +154,6 @@
 
 % Class number.
 \newcounter{chapterplusone}
-\setcounter{chapterplusone}{\value{chapter}}
-\stepcounter{chapterplusone}
 \newcommand{\ClassNumber}{\thechapter}
 \newcommand{\ClassNumberPlusOne}{\thechapterplusone}
 \newcommand{\SetClassNumber}[1]{%