diff --git a/MagickCore/timer.c b/MagickCore/timer.c
index 5bba074..a9a1fe6 100644
--- a/MagickCore/timer.c
+++ b/MagickCore/timer.c
@@ -51,11 +51,8 @@
 /*
   Define declarations.
 */
-#if defined(macintosh)
-#define CLK_TCK  CLOCKS_PER_SEC
-#endif
-#if !defined(CLK_TCK)
-#define CLK_TCK  sysconf(_SC_CLK_TCK)
+#if !defined(CLOCKS_PER_SEC)
+#define CLOCKS_PER_SEC  100
 #endif
 
 /*
@@ -195,12 +192,12 @@
   struct tms
     timer;
 
-  return((double) times(&timer)/CLK_TCK);
+  return((double) times(&timer)/CLOCKS_PER_SEC);
 #else
 #if defined(MAGICKCORE_WINDOWS_SUPPORT)
   return(NTElapsedTime());
 #else
-  return((double) clock()/CLK_TCK);
+  return((double) clock()/CLOCKS_PER_SEC);
 #endif
 #endif
 }
@@ -450,12 +447,12 @@
     timer;
 
   (void) times(&timer);
-  return((double) (timer.tms_utime+timer.tms_stime)/CLK_TCK);
+  return((double) (timer.tms_utime+timer.tms_stime)/CLOCKS_PER_SEC);
 #else
 #if defined(MAGICKCORE_WINDOWS_SUPPORT)
   return(NTUserTime());
 #else
-  return((double) clock()/CLK_TCK);
+  return((double) clock()/CLOCKS_PER_SEC);
 #endif
 #endif
 }