diff --git a/R/read.px.R b/R/read.px.R
index 9be8bc1..ded958c 100644
--- a/R/read.px.R
+++ b/R/read.px.R
@@ -31,7 +31,7 @@
 #################################################################
 
 read.px <- function(filename, encoding = NULL, 
-                    na.strings = c('"."', '".."', '"..."', '"...."', '":"')) {
+                    na.strings = c('"."', '".."', '"..."', '"...."', '"....."', '":"')) {
 
     ## auxiliary functions ##