--- a/FXAnalyse.c	Fri Dec 13 17:04:28 2013 +0100
+++ b/FXAnalyse.c	Mon Dec 16 19:50:20 2013 +0100
@@ -162,22 +162,23 @@
 char * thousands(char *buffer, int size, char *fmt, double val)
 {
 	// compute how many separators we need
-	int nsep = (int)(log10(fabs(val)+1.0))/3;
+	#pragma DisableFunctionRuntimeChecking log10
+	int nsep = log10(fabs(val)) / 3;
 	// format value
 	int len = snprintf(buffer, size, fmt, val);
-	char *src = buffer + len + 1;
+	char *src = buffer + len;
 	char *dst = src + nsep;
 	// copy till decimal separator
 	while (*src != '.')
 		*dst-- = *src--;
-	// copy till the beginning inserting separators
+	// the next char is the decimal separator
 	int n = -1;
-	while (1) {
+	// copy till src and dst point to the same location
+	while (src != dst) {
 		*dst-- = *src--;
+		// insert separator
 		if (isdigit(*src) && (++n) && ((n % 3) == 0))
 			*dst-- = ' ';
-		if (src == buffer)
-			break;
 	}
 	return buffer;
 }